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In the recent years, the pregnancy trend among women with Congenital Heart Disease (CHD) has increased; this has leaded to a growing demand for specialized care both in mother and in children. Although pregnancy is often well tolerated, maternal CHD may affect in some cases a maladaptive hemodynamic response carrying additional risks of cardiovascular events like arrhythmias, heart failure and, in rare cases, death. The impaired utero-placental perfusion due to maternal cardiac status may result in placental dysfunction, which may be associated with fetal growth restriction, preeclampsia, premature birth and perinatal morbidity. Systemic Right Ventricle (SRV) is one of the main conditions under which pregnancy is challenging. The sub-aortic position of morphological Right Ventricle (RV) is "physiologically" predisposed to fail at the adult age and may be potentially inadequate to support the hemodynamic stress of the pregnancy. Current literature about pregnancy in women with SRV consists of small retrospective series not providing conclusive evidence about the feasibility of a successful pregnancy outcomes. In addition, the long-term effects of pregnancy on SVR are not still adequately investigated and it remains unclear if maternal complications reported are due to pregnancy or to natural history of SVR. The aim of this paper is to offer a critical review of the knowledges at regard and to provide a practice update on the risk assessment and the pregnancy management in women with SRV in order to support the decision making and to optimize outcomes in these patients., Competing Interests: Declaration of Competing Interest None., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Background: Patients with systemic right ventricle (sRV), including transposition of great arteries (TGA) after atrial switch procedure and congenitally corrected transposition of great arteries (ccTGA), may require anticoagulation for thromboembolism (TE) prevention. In the absence of data on non-vitamin K antagonist oral anticoagulants (NOACs), vitamin K antagonists (VKAs) remain the agent of choice. We investigated the safety, efficacy and feasibility of NOACs treatment in adults with sRV in a worldwide study., Methods: This is an international multicentre prospective study, using data from the NOTE registry on adults with sRV taking NOACs between 2014 and 2019. The primary endpoints were TE and major bleeding (MB). The secondary endpoint was minor bleeding., Results: A total of 76 patients (42.5 ± 10.0 years, 76% male) with sRV (74% TGA, 26% ccTGA) on NOACs were included in the study. During a median follow-up of 2.5 years (IQR1.5-3.9), TE events occurred in 3 patients (4%), while no MB episodes were reported. Minor bleeding occurred in 9 patients (12%). NOAC treatment cessation rate was 1.4% (95%CI:0.3-4%) during the first year of follow-up. All the patients with TE events had a CHA 2 DS 2 -VASc score ≥ 2 and impaired sRV systolic function at baseline. The total incidence of major events during follow-up was significantly lower compared to historical use of VKAs or aspirin before study inclusion (1.4% (95%CI:0.29-4%) vs 6,9% (95%CI:2.5-15.2%); p = .01)., Conclusions: In this prospective study, NOACs appear to be well-tolerated, with excellent efficacy and safety at mid-term in patients with sRV., Competing Interests: Declaration of Competing Interest Dr. B.J. Bouma has received restricted research grant from Bristol-Myers Squibb and Pfizer. Prof. B.J.M. Mulder has received restricted research grants from Ingelheim-Boehringer, Bayer, and Daiichi Sankyo. The other Authors report no relationships that could be construed as a conflict of interest., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Background: Combinations of therapies are currently recommended for patients with severe pulmonary arterial hypertension (PAH), and excellent results have been reported with triple upfront combination of these drugs. We evaluated the effects of this approach on right ventricular (RV) function and outcome in patients with severe PAH., Methods: Twenty-one patients (age, 44 ± 15 years) with newly diagnosed high-risk idiopathic PAH that was nonreversible by the inhalation of nitric oxide were treated upfront with a combination of ambrisentan, tadalafil, and subcutaneous treprostinil between 2014 and 2018. Clinical evaluation, World Health Organization functional class, 6-min walk distance, biomarkers, echocardiography, and right-sided heart catheterization data were recorded at baseline and during follow-up., Results: At a median follow-up of 2 years, all patients were still alive. The Registry to Evaluate Early and Long-term Pulmonary Arterial Hypertension Disease Management score decreased from 10 ± 1 to 5 ± 1, right-sided atrial pressure decreased from 13 ± 3 to 5 ± 2 mm Hg, mean pulmonary artery pressure decreased from 60 ± 9 to 42 ± 5 mm Hg, pulmonary vascular resistance (PVR) decreased from 16.4 ± 4.4 to 5.5 ± 1.3 Wood units, N-terminal pro-brain natriuretic peptide decreased from 3,379 ± 1,921 to 498 ± 223 pg/mL, and World Health Organization functional class decreased from 3.4 ± 0.5 to 2.0 ± 0.4 (all P < .001). Cardiac index increased from 1.8 ± 0.3 to 3.5 ± 0.8 L/min/m 2 and 6-min walk distance increased from 158 ± 130 to 431 ± 66 m (both P < .001). Echocardiography showed decreased right-sided atrial and RV areas, improved left ventricular eccentricity index, and increased fractional area change (all P < .001) in proportion to treatment-induced decrease in PVR., Conclusions: Triple upfront combination therapy with ambrisentan, tadalafil, and subcutaneous treprostinil in severe nonreversible PAH is associated with considerable clinical and hemodynamic improvement and right-sided heart reverse remodeling., (Copyright © 2019 American College of Chest Physicians. Published by Elsevier Inc. All rights reserved.)

Background: Patent foramen ovale (PFO) closure after a cryptogenic cerebral ischemic event is a routinely procedure. The most used device is Amplatzer™ PFO Occluder 25 mm, but PFOs with complex anatomy require larger device for closure. We compared Amplatzer™ Septal Occluder (ASO) device versus Amplatzer™ PFO Occluder 30 or 35 mm (A-PFO 30/35) about the safety of procedure and the presence of residual shunt during the follow-up., Methods: From June 2002 to July 2016, 355 patients (pts) with PFO undergone closure at our institution. Among these ones, 70 pts (19.7%) had a PFO with complex anatomy and a single device with greater diameter was implanted. In these cases, the following devices were used: Gore® Septal Occluder (GSO) in 4 pts; ASO device in 33 pts (group I) and A-PFO 30/35 in 33 pts (group II). Patients treated with GSO device were excluded by our analysis., Results: Comparing group I and group II, there weren't complications during the procedures. Two patients of group II were lost at follow-up. At last follow-up, 1 pt of group I (3%) and 10 pts of group II (32.3%) had a residual shunt (p < 0.01). 7 of 10 pts of group II and the only 1 of group I with residual shunt underwent a complete closure by Amplatzer™ Vascular Plug (AVP) devices., Conclusions: ASO devices and A-PFO 30/35 devices are both safe to close complex PFO; but A-PFO 30/35 is associated with a more incidence of residual shunt., (Copyright © 2018 Elsevier B.V. All rights reserved.)

Background: The subcutaneous implantable cardioverter defibrillator (S-ICD) is a relatively novel alternative to the transvenous ICD for the treatment of life-threatening ventricular arrhythmias, and is currently used in the clinical practice of several centers. The aim of this analysis was to describe current Italian practice regarding S-ICD implantation and its evolution over the years., Methods: We analyzed 607 consecutive patients (78% male, 48 ± 16 years) who underwent S-ICD implantation in 39 Italian centers from 2013 to 2017., Results: Structural cardiomyopathy was present in 78% of patients and 30% of patients received their device for secondary prevention. The proportion of patients with dilated cardiomyopathy and with left ventricular ejection fraction ≤35% increased from ≤2014 to 2017 (from 38% to 58%, from 33% to 53%, respectively; both p < 0.05). Almost all procedures (97%) were performed in electrophysiology laboratories. Over the last 4 years, the 2-incision implantation technique has been widely adopted, with sub- or inter-muscular positioning of the generator, under local anesthesia or deep sedation (≤2014 versus 2017: all p < 0.001). Defibrillation testing was performed in 81% of patients. Shock energy of ≤65 J was successful in 93.9% of patients and the overall cardioversion success rate at ≤80 J was 99.8%., Conclusions: Our analysis confirmed that the S-ICD continues to be preferentially used in specific patients (younger, less frequently with dilated cardiomyopathy and low ejection fraction.). Nonetheless, we noted a trend toward the wider use of S-ICD in patients with dilated cardiomyopathy and systolic dysfunction over the years. Novel approaches have been adopted while the acute efficacy of the system has remained stably high., (Copyright © 2018. Published by Elsevier B.V.)

Aim: To determine whether right atrial (RA) function has prognostic value in patients with idiopathic pulmonary arterial hypertension (PAH)., Methods and Results: Overall, 104 patients (70 female, mean age 58±13years) with idiopathic PAH underwent standard Doppler echocardiography and strain and strain rate (SR) analysis before right heart catheterization. At a mean follow-up of 22±7months, 30 patients (29%) had clinical worsening. On Cox multivariable proportional-hazards regression analysis, RA reservoir function measured as peak longitudinal SR (hazard ratio [HR] 0.5; P<0.0001), RA area (HR 1.2; P<0.01), right ventricular (RV) SR (HR 0.6; P<0.0001), cardiac index (HR 0.79; P<0.01), and mixed venous oxygen saturation (HR 0.82; P<0.01) were found to be independent correlates of cardiac events. A RA SR reservoir cut-off value of <1.2s -1 and a RV SR cut-off value of <1s -1 well identified patients at higher risk of clinical worsening (sensitivity 85.5%; specificity 90.4%; test accuracy 88.8%). In particular, event rates and mean survival time free of clinical worsening were: 6.1% and 23.5±2.2months in patients with normal RA and RV SR; 45% and 20.9±5.5months in patients with impaired RA and normal RV SR; 56.2% and 17.7±6.6months in patients with normal RA and impaired RV SR; and 87.5% and 12.9±7.6months in patients with impairment of both RA and RV SR., Conclusion: Our data suggest that RA function has prognostic value in idiopathic PAH, where a poorer RA function, as explored by strain and SR analysis, is associated with a worse outcome., (Copyright © 2017 Elsevier B.V. All rights reserved.)

Percutaneous closure is widely recognized as the first therapeutic option in the majority of cases of secundum atrial septal defect (ASD) because of its high effectiveness and safety. Nonetheless, with the progressive increase of implanted devices and follow-up duration, several adverse events, some of them potentially life-threatening, have been reported. We report the case of an asymptomatic aortic erosion that occurred 13 years after the procedure. The main feature of our case is the very late occurrence of a life-threatening asymptomatic complication of ASD percutaneous closure, which should prompt lifelong surveillance in this population., (Copyright © 2016 Canadian Cardiovascular Society. Published by Elsevier Inc. All rights reserved.)

Background: Fluid challenge may help in the differential diagnosis between pre- and postcapillary pulmonary hypertension (PH). However, the test is still in need of standardization and better defined clinical relevance., Methods: Two hundred twelve patients referred for PH underwent a right-sided heart catheterization with measurements before and after rapid infusion of 7 mL/kg of saline. PH was defined as mean pulmonary artery pressure ≥ 25 mm Hg, and postcapillary PH was defined as pulmonary artery wedge pressure (PAWP) > 15 mm Hg. An increase in PAWP ≥ 18 mm Hg was considered diagnostic for postcapillary PH. At baseline, 66 patients received a diagnosis of no PH; 22, of postcapillary PH; and 124, of precapillary PH (mostly pulmonary arterial hypertension)., Results: After fluid challenge, five of 66 patients with no PH (8%) and eight of 124 with precapillary PH (6%) had the diagnosis reclassified as postcapillary PH. Fluid challenge was associated with an increase in PAWP by 7 ± 2 mm Hg in postcapillary PH and 3 ± 1 mm Hg in both precapillary PH and no-PH groups. Between-group differences were significant, but there was overlap. There were no adverse events related to fluid challenge. Prediction bands calculated from quadratic fits of the PAWP responses in pooled control subjects with no PH and patients with precapillary PH helped confirm 18 mm Hg as the cutoff for diagnosing postcapillary PH., Conclusions: Fluid challenge with 7 mL/kg saline increases PAWP, more in postcapillary than in precapillary PH or in control subjects with no PH. A cutoff value of 18 mm Hg allows reclassification of 6% to 8% of patients with precapillary PH or normal hemodynamic characteristics at baseline., (Copyright © 2016 American College of Chest Physicians. Published by Elsevier Inc. All rights reserved.)

Background: Echocardiographic studies have contributed to progress in the understanding of the pathophysiology of the pulmonary circulation and have been shown to be useful for screening for and prognostication of pulmonary hypertension, but are considered unreliable for the diagnosis of pulmonary hypertension. We explored this apparent paradox with rigorous Bland and Altman analysis of the accuracy and the precision of measurements collected in a large patient population., Methods: A total of 161 patients referred for a suspicion of pulmonary hypertension were prospectively evaluated by a Doppler echocardiography performed by dedicated cardiologists within 1 h of an indicated right heart catheterization., Results: Nine of the patients (6%) were excluded due to an insufficient signal quality. Of the remaining 152 patients, 10 (7%) had no pulmonary hypertension and most others had either pulmonary arterial hypertension (36%) or pulmonary venous hypertension (40%) of variable severities. Mean pulmonary artery pressure, left atrial pressure and cardiac output were nearly identical at echocardiography and catheterization, with no bias and tight confidence intervals, respectively ± 3 mm Hg, ± 5 mm Hg and ± 0.3 L/min. However, the ± 2SD limits of agreement were respectively of + 19 and - 18 mm Hg for mean pulmonary artery pressure, + 8 and - 12 mm Hg for left atrial pressure and + 1.8 and - 1.7 L/min for cardiac output., Conclusions: Doppler echocardiography allows for accurate measurements of the pulmonary circulation, but with moderate precision, which explains why the procedure is valid for population studies but cannot be used for the individual diagnosis of pulmonary hypertension., (© 2013.)

Background: Pulmonary arterial hypertension (PAH) after shunt closure is associated with a poor prognosis. The aim of this study was to assess retrospectively the hemodynamics of patients developing PAH after shunt closure., Methods: Hemodynamic data obtained by right heart catheterization (RHC) performed at baseline and after shunt closure were analyzed., Results: Twenty-two patients, 13 with atrial septal defect (ASD), 6 with ventricular septal defect (VSD), 1 with patent ductus arteriosus, 1 with both ASD and VSD, and 1 with complete atrio-ventricular canal have been considered. The mean age at closure was 25.3±20.1 years (range of 3 months to 56.7 years), and the mean age at PAH diagnosis was 37.0±20.8 years (range of 5 to 61.2 years). The time delay between shunt closure and PAH diagnosis was 140.2±100.2 months. At baseline RHC, hemodynamic data were as follows: pulmonary vascular resistance (PVR) of 8.6±2.6 Wood units, PVR index (PVRi) of 10.1±2.7 Wood units∗m(2), mean pulmonary arterial pressure of 43.7±9.7 mmHg, PVR to systemic vascular resistance ratio (PVR/SVR) of 0.70±0.23, and Qp/Qs of 1.6±0.4. In particular, 18/22 (81%) had PVR≥5 Wood units, 21/22 (95%) PVRi≥6 Wood units∗m(2), 21/22 (95%) PVR/SVR≥0.33, and 11/22 (50%) Qp/Qs≤1.5. During the follow-up, 5/22 (22%) patients died and one patient underwent successful double lung transplantation., Conclusions: High baseline values of PVR (≥5 Wood units), PVRi (≥6 Wood units∗m(2)) and PVR/SVR (≥0.33) are common findings in patients who develop PAH late after shunt closure. Large prospective clinical trials are needed to establish the safe limits for shunt closure., (© 2013.)

Background: Oral bosentan is effective in pulmonary arterial hypertension (PAH) related to congenital heart disease (CHD). In patients with Down's syndrome, the effect of bosentan is largely unknown. Aim of the study was to evaluate the long-term effects of bosentan in adult patients with CHD-related PAH with and without Down's syndrome., Methods: WHO functional class, resting oxygen saturation, 6-minute walk test (6 MWT) and hemodynamics were assessed at baseline and after 12 months of bosentan therapy in patients with CHD-related PAH with and without Down's syndrome., Results: Seventy-four consecutive patients were enrolled: 18 with and 56 without Down's syndrome. After 12 months of bosentan therapy, both with and without Down's syndrome patients showed an improvement in WHO functional class (Down: 2.5 ± 0.5 vs 2.9 ± 0.6, p=0.005; controls: 2.5 ± 0.5 vs 2.9 ± 0.5, p=0.000002), 6-minute walk distance (Down: 288 ± 71 vs 239 ± 74 m, p=0.0007; controls: 389 ± 80 vs 343 ± 86 m, p=0.00003), and hemodynamics (pulmonary flow, Down: 4.0 ± 1.6 vs 3.5 ± 1.4 l/m/m(2), p=0.006; controls: 3.5 ± 1.4 vs 2.8 ± 1.0 l/m/m(2), p=0.0005; pulmonary to systemic flow ratio, Down: 1.4 ± 0.7 vs 1.0 ± 0.4, p=0.003; controls: 1.1 ± 0.7 vs 0.9 ± 0.3, p=0.012; pulmonary vascular resistance index, Down: 15 ± 9 vs 20 ± 13 WUm(2), p=0.007; controls: 2 0 ± 10 vs 26 ± 15 WUm(2), p=0.002). No differences in the efficacy of therapy were observed between the two groups., Conclusions: Bosentan was safe and well tolerated in adult patients with CHD-related PAH with and without Down's syndrome during 12 months of treatment. Clinical status, exercise tolerance, and pulmonary hemodynamics improved, regardless of the presence of Down's syndrome., (Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.)

Background: Bicuspid aortic valve (BAV) represents the most common cardiac congenital malformation in the adult age. It is frequently associated with dilatation, aneurysm and dissection of the ascending aorta. The purpose of the following study was to evaluate in patients with BAV: 1) the elastic properties of the ascending aorta, 2) the mechanical function of the left ventricle and 3) stiffness, elasticity and strain of the epi-aortic vessels wall., Methods: Forty BAV patients (28M/12F; age 20.9 ± 4.7 years; range 17-26) with no or mild valvular impairment were recruited with 40 control subjects (25M/15F; age 23.4 ± 3.4 years; range 15-31) matched for age, gender and body surface area (BSA). Aortic strain, aortic distensibility (AoDIS) and aortic stiffness index (AoSI) were derived. Left ventricular strain was acquired. Elastic properties of epi-aortic vessels were evaluated., Results: BAVs vs. controls had increased systolic and diastolic aortic diameters (p<0.001). Aortic strain (%) was lower in BAVs than in controls (8.3 ± 3.6 vs. 11.2 ± 2.6; p<0.001) as well as AoDIS (10(-6)cm(2)dyn(-1)) (6.5 ± 2.8 vs. 8.8 ± 2.9; p=0.002), while AoSI was greater in BAVs (6.4 ± 3.5 vs. 3.9 ± 1.2; p<0.001). Both AoDIS and aortic strain were related to aortic size in BAVs and controls. Left ventricular longitudinal (p=0.01), circumferential (p=0.01) and radial (p<0.001) strain (%) were lower in BAVs. No significant differences were found in elastic properties of epi-aortic vessels., Conclusions: Bicuspid aortic valve is associated with an increased aortic stiffness and with a reduction of the aortic and left ventricular deformation properties. Epi-aortic vessels do not seem to be interested by the disease. The use of an echocardiographic method that can estimate the degree of aortic and left ventricular remodeling can provide great benefits in the selection of patients with BAV to be treated and in determining the time for beginning drug therapy., (Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.)

Objectives: The aim of the present study was to evaluate the safety, tolerability, clinical and haemodynamic impact of add-on sildenafil in patients with congenital heart disease (CHD)-related pulmonary arterial hypertension (PAH) and Eisenmenger physiology after failure of oral bosentan therapy., Methods: Thirty-two patients with CHD-related PAH (14 male, mean age 37.1 ± 13.7 years) treated with oral bosentan underwent right heart catheterization (RHC) for clinical worsening. After RHC, all patients received oral sildenafil 20mg thrice daily in addition to bosentan. Clinical status, resting transcutaneous oxygen saturation (SpO(2)), 6-minute walk test (6MWT), serology and RHC were assessed at baseline (before add-on sildenafil) and after 6 months of combination therapy., Results: Twelve patients had ventricular septal defect, 8 atrio-ventricular canal, 6 single ventricle, and 6 atrial septal defect. Twenty-eight/32 had Eisenmenger physiology and 4 (all with atrial septal defect) did not. All patients well tolerated combination therapy. After 6 months of therapy, an improvement in clinical status (WHO functional class 2.1 ± 0.4 vs 2.9 ± 0.3; P=0.042), 6-minute walk distance (360 ± 51 vs 293 ± 68 m; P=0.005), SpO(2) at the end of the 6MWT (72 ± 10 vs 63 ± 15%; P=0.047), Borg score (2.9 ± 1.5 vs 4.4 ± 2.3; P=0.036), serology (pro-brain natriuretic peptide 303 ± 366 vs 760 ± 943 pg/ml; P=0.008) and haemodynamics (pulmonary blood flow 3.4 ± 1.0 vs 3.1 ± 1.2l/min/m(2), P=0.002; pulmonary vascular resistances index 19 ± 9 vs 24 ± 16 WU/m(2), P=0.003) was observed., Conclusions: Addition of sildenafil in adult patients with CHD-related PAH and Eisenmenger syndrome after oral bosentan therapy failure is safe and well tolerated at 6-month follow-up, resulting in a significant improvement in clinical status, effort SpO(2), exercise tolerance and haemodynamics., (Copyright © 2010 Elsevier Ireland Ltd. All rights reserved.)

Background: Because transposition of great arteries (TGA) patients who underwent atrial switch repair (AS) remain asymptomatic for decades before development of symptomatic heart failure, there may be some clinical value to preclinical detection of ventricular dysfunction. Detection of systemic right ventricular (RV) dysfunction in patients who are asymptomatic may prompt early initiation of heart failure therapy and more frequent clinical follow-up., Aim: The objective of this study was to characterize longitudinal and transverse systolic function of the systemic RV using two-dimensional (2D) strain in patients with TGA after AS repair and to correlate these parameters with their exercise capacity., Methods: The study population consisted of 26 patients (20±6 years) with TGA after AS operation. Conventional echocardiography and bidimensional strain were performed on consecutive patients reporting to the out patient congenital heart disease clinic. Twenty-four healthy, age-matched individuals were used as control subjects. Analysis was performed on the non-systemic RVs of the control group. All the studied patients underwent treadmill exercise testing according to the Bruce II protocol., Results: RV longitudinal 2D-strain in controls showed a base to apex gradient, while in patients was homogeneously reduced. Also RV transverse strain (i.e the radial deformation assessed by the apical 4 chamber view) showed a base to apex gradient in controls, while in patients was significantly increased in the mid and apical segments. In the systemic RV free wall, transverse strain was greater than longitudinal strain (p<0.0001), opposite from findings in the normal RV free wall (p: NS). Of interest, in AS-TGA patients we found a strong correlation between RV transverse 2D strain and exercise capacity (p<0.0001; R: 0.80). At multivariate analysis (including age, degree of tricuspid regurgitation, TAPSE, RV area fractional change, RV visually estimated ejection fraction, RV global longitudinal strain and RV global transverse strain) the best predictor of exercise capacity in AS-TGA patients was transverse 2D strain (p<0.0001)., Conclusions: In AS-TGA patients there is a shift from a predominant longitudinal shortening to a predominant transverse thickening. The transverse thickening assessed by 2D transverse strain is correlated to exercise capacity of these patients. In the follow up of AS-TGA patients the monitoring of RV transverse myocardial deformation properties should be considered more than the simple evaluation of RV longitudinal function., (Copyright © 2009 Elsevier Ireland Ltd. All rights reserved.)

Aim: To study, by conventional echocardiography, left ventricular remodelling and function in master athletes, hypertension and hypertrophic cardiomyopathy., Methods: We studied 30 master athletes (MA; soccer players; mean age 43.9+/-5.9), 24 subjects with essential hypertension (HYP; 46.6+/-6), 20 patients with hypertrophic cardiomyopathy (HCM; 42.2+/-9) and 30 normal individuals (CG; 43.4+/-5). An integrated M-mode/two-dimensional echocardiographic analysis was performed to determine chambers dimensions, relative wall thickness (RWT) and left ventricular mass (LVM), indexed to height in meters raised to the power of 2.7 (LVM/h(2.7)). Cut-off levels for LVM/h(2.7) and RWT were defined to assess 4 different patterns of LV geometric remodelling. In addition, we measured indexes of global systolic performance and indexes of global diastolic function., Results: LV wall thickness and LV end-diastolic dimensions were higher in MA than controls, but significantly lower than other groups. LVH/h(2.7) was increased in 79% of HYP and in 95% of HCM, but was within the normal limits in MA. LV geometry was normal in 22 out of 30 MA (73%), while the remaining (8 athletes, 27%) showed a concentric remodelling. Systolic function (FS and EF) was normal in MA, but was slightly reduced in HYP and increased in HCM. Analysis of diastolic function showed an abnormal relaxation pattern in all HYP and 95% of HCM, but was normal in all MA. The ratio between peak filling rate and stroke volume (PFR/SV), a relatively independent index of diastolic function, was significantly greater in hypertensive patients with normal LV remodelling compared to those without it (4+/-0.39 vs. 4.91+/-0.19; P = 0.0002)., Conclusion: MA showed lower values of wall thickness, LV dimensions and LV mass compared with HYP and HCM. Despite an abnormal remodelling, all the athletes showed a normal systolic and diastolic function. The differential diagnosis between MA, HYP and HCM is feasible by accurate, comprehensive standard Doppler echocardiography.

Background: Congenital heart disease (CHD) is the most common malformation in the fetal and neonatal period but little is known about its cause. The distribution analysis of CHD in dizygotic twins could provide a useful tool to evaluate the role of genetic and environmental factors in the development of CHD. Dizygotic twins are siblings with different genes, growing together in the same womb., Aim of Study: To investigate the occurrence of CHD in a large sample of dizygotic twins of nonconsanguineous healthy parents, comparing the data from non-twin patients., Methods: From January 1999 to December 2002, we enrolled 1743 CHD patients with, at least 1 sibling, and 66 pairs of dizygotic twins, referred to our tertiary center. The diagnosis of CHD was based on clinical and echocardiographic evaluation., Results: Considering only the sibling nearest in age for each non-twin patient the recurrence was 67/1743 (3.8%). Among these 67 patients, 35 (52.2%) had a sibling with the same or similar CHD. Conversely, considering all 1886 siblings, recurrence of CHD in the non-twin group was 70/1743 (4%). Of the 70 patients, 36 (36/70, 51.4%) had a sibling with the same suspected pathogenic mechanism of CHD. In 9/66 pairs of twins (13.6%), both siblings had a CHD. In the nine pairs of twins in whom both siblings had a CHD, the percentage of concordance (based on the suspected pathogenic mechanism) for CHD was 100% (p<0.05)., Conclusions: Our findings suggest that the higher recurrence and concordance of CHD found in dizygotic twins could depend on some poorly identified environmental risk during the pregnancy.

Background: Diagnostic assessment and treatment have been described in detail in symptomatic WPW syndrome, but little information exists about significance and prognosis of an incidentally found ventricular pre-excitation (VPE) in asymptomatic children. The aim of the study was to evaluate, retrospectively, the role of electrophysiological study (EPS) in the assessment of the arrhythmic risk in asymptomatic patients with VPE., Material and Methods: Sixty-two asymptomatic children and adolescents (38 M/24 F, aged 9.8+/-5.1 years) referred to our Division between 1996 and 2002 for an incidentally found VPE underwent an EPS for arrhythmic risk stratification. The following parameters were examined: anterograde effective refractory period of the accessory pathway (AP), the 1-to-1 conduction over the AP, the inducibility of atrio-ventricular re-entrant tachycardia (AVRT) and the inducibility of atrial fibrillation (AF) with measurement of minimal RR between two consecutive preexcitated QRS complexes, the average RR interval of all cycles, and the percentage of preexcitated QRS complexes., Result: During the EPS, 36 patients (58.1%) experienced sustained SVT. The tachycardia was initiated in the basal state in 22 patients and after isoproterenol in the other 14. Orthodromic AVRT (cycle length 305.9+/-48.5 ms) was recorded in 29 patients. In three patients, both orthodromic and antidromic AVRT were recorded, with different cycle length (CL). Antidromic AVRT alone (CL 239.5+/-13.7 ms) was recorded in four patients. AF was recorded in nine patients: in six patients, it was recorded after the induction of orthodromic or antidromic AVRT, in the other three cases AF was the first and only arrhythmic event. The minimal RR between two consecutive pre-excitated QRS ranged between 250-230 ms (mean 237.5+/-9.6 ms). In the 26 patients who presented no induced sustained tachycardia in the EPS, the 1:1 conduction over the AP ranged between 210 and 600 ms (mean 279.6+/-75.2 ms)., Conclusions: Electrophysiological evaluation remains the gold standard for assessing risk of life-threatening arrhythmias in patients with VPE. However, a high proportion of healthy children and adolescents with VPE can experience sustained AVRT and/or AF during EPS. These results raise questions about the necessity of an aggressive treatment approach to prevent those "rare" cases of sudden death.

Aim of the Study: To detect in adult patients late after repair of Tetralogy of Fallot (TOF) possible correlation between myocardial parameters assessed at rest by Tissue Doppler (TD) and cardiac performance during physical effort., Methods: Doppler echo, treadmill test and pulsed TD of both mitral and tricuspid annulus were performed in 25 healthy subjects and in 40 adult patients who had undergone surgery for TOF at a mean age of 1.4+/-0.5 years. Exclusion criteria were echocardiographic evidence of residual pulmonary, either stenosis or regurgitation. By use of TD, the following parameters were assessed: systolic peak velocities (Sm), pre-contraction time, contraction time, early (E(m)) and late (A(m)) diastolic velocities, E(m)/A(m) ratio, relaxation time. By treadmill test, we measured: maximal heart rate (HR), systolic blood pressure (SBP), rate-pressure product, maximal workload, time duration of the exercise., Results: the two groups were comparable for left ventricular measurements and for all transmitral and transtricuspid Doppler indexes, while tricuspid ring diameter was increased in TOF. TD analysis showed in TOF lower S(m), E(m) and E(m)/A(m) ratio and prolonged PCT(m) and Rt(m) at tricuspid annulus level, despite comparable TD mitral annulus indexes. By treadmill test, TOF showed reduced time of exercise, number of METS reached and rate-pressure product. Multiple linear regression models evidenced in TOF independent positive association between tricuspid Em velocity and time of exercise (p<0.0001), achieved METS at peak effort (p<0.001) and rate-pressure product (p<0.001). An E(m) peak velocity of tricuspid annulus lower than 0.13 m/s showed 90% sensitivity and 93% specificity in identifying TOF patients unable to perform maximal exercise test., Conclusions: despite normal Doppler parameters, adult patients late after correction of TOF showed impaired right ventricular myocardial function. In these patients pulsed TD may be taken into account as a valuable supporting tool to predict the effort response and possibly to assess long-term follow-up of cardiac functional reserve.

Background: Basic research and animal experiments have shown electrophysiological changes during or after changes in mechanical loading. Electrical instability following mechanical stretch has been observed as development of after-depolarisation and dispersion of refractoriness and repolarisation. The aim of the present study was to evaluate the presence of the mechano-electrical feedback in humans, assessing the ventricular repolarisation changes following acute changes in left ventricular pressure., Material and Methods: The study group comprised 30 consecutive patients (22 M and 8 F, aged 2 days-24 years) affected by severe congenital aortic stenosis and 30 patients (20 M and 10 F, aged 6 months-16 years) affected by severe coartaction of aorta. Ventricular repolarisation was evaluated before and after percutaneous balloon valvuloplasty and angioplasty in terms of absolute measures (JT, JTc, QT, QTc) and in terms of dispersion across the myocardium: QT and QTc dispersion (QTD, QTcD), JT and JTc dispersion (JTD and JTcD) and T-peak to T-end interval (Tp-Te)., Results: Patients with severe aortic stenosis and patients with aortic coartaction showed a significant decrease in dispersion of ventricular repolarisation time indexes (QTD, QTcD, JTD, JTcD and Tp-Te) following valvuloplasty and angioplasty., Conclusions: Changes in hemodynamic loading can also produce electrophysiological effects in humans. Acute reduction in left ventricular pressure overload following balloon valvuloplasty and angioplasty, decreases electrical instability, as expressed by the reduction across the myocardium of the dispersion of ventricular repolarisation.

Aim: The aim of the study was to evaluate in 263 competitive athletes possible correlations between changes induced by different sport activities in left ventricular (LV) structure and cardiac response during maximal physical effort., Methods: A total of 160 top-level endurance athletes (ATE; swimmers, runners; 28+/-4 years; 98 male) and 103 strength-trained athletes (ATS; weight-lifters, body-builders; 27+/-5 years; male), selected on the basis of training protocol (dynamic vs. static exercise), underwent standard Doppler echocardiography, heart rate variability analysis and maximal exercise stress test by bicycle ergometry. M- and B-mode echocardiographic LV measurements were determined at rest, while the following functional indexes were assessed during effort: maximal heart rate (HR), maximal systolic blood pressure (SBP) and maximal workload (Watts reached by bicycle test)., Results: The two groups were comparable for age and sex, but ATS at rest showed higher HR, SBP, and body surface area (BSA). By echo analysis, LV mass index and ejection fraction did not significantly differ between the two groups. However, ATS showed increased sum of wall thickness (septum+posterior wall), relative wall thickness and LV end-systolic stress, while LV stroke volume and LV end-diastolic diameter (P<0.01) were greater in ATE. HR variability analysis underlined in ATE increased indexes of vagal tone (P<0.01). During maximal physical effort, ATE showed a better functional capacity, with greater maximal workload (P<0.001) reached with lower maximal HR and SBP. After adjusting for HR, age, sex, BSA and SBP, distinct multiple linear regression models evidenced in ATE independent associations of maximal effort workload with LV end-diastolic diameter (P<0.001), HR (P<0.001) at rest and LV end-systolic stress (P<0.01) were found in ATE. On the other hand, independent direct correlation of SBP max during effort with sum of wall thickness (P<0.001), BSA (P<0.05) and LV end-systolic stress (P<0.001) was evidenced in ATS., Conclusions: LV structural changes in competitive athletes represent adaptation to hemodynamic overload induced by training and are consistent with different kinds of sport activity. Work capacity during exercise is positively influenced by preload increase in ATE, while increased afterload due to isometric training in ATS determines higher systemic resistance during physical effort.

The aim of the study was to evaluate by Doppler tissue imaging (DTI) the combined effects of atrio-ventricular (AV) delay and heart rate (HR) changes on global and segmental right (RV) and left (LV) ventricular diastolic function in 15 patients with dual-chamber pacemakers paced in the DDD mode. RV and LV inflow velocities and regional systolic and diastolic pulsed-wave (PW) DTI parameters were analyzed at four different pacing modes: (1) HR 70 beats/min, AV delay 125 ms; (2) HR 70 beats/min, AV delay 188 ms; (3) HR 89 beats/min, AV delay 125 ms; (4) HR 89 beats/min, AV delay 188 ms. For each pacing mode selected, RV diastolic filling velocities always prevailed over LV ones. As for RV and LV adaptation to the four different stimulation protocols, a higher paced rate and a prolonged AV delay caused across both the AV valves a decrease of E wave and of E/A ratios. The intersegmental comparison of PW-DTI parameters outlined that RV free wall exhibited significantly higher peak systolic (Sm) and early-diastolic (Em) wall velocities, and longer systolic ejection time. Considering separately RV and LV segmental physiology at the four programmed pacing modes, an increase in HR determined a progressive shortening of systolic ejection times in all the segments analyzed. Moreover, in each region the Em/Am ratio decreased with higher HR and longer AV delay. Conversely, Em encountered a progressive reduction in RV free wall, while remaining quite unchanged in all the LV regions. Both ventricles shared a similar pattern of global and regional adaptation to programmed HR and AV delay modifications, consisting in a progressive greater contribution of late diastole to ventricular filling at higher HR and more prolonged AV delay. However, at a regional level the right ventricle exhibited higher systolic and diastolic wall velocities than all left ventricular regions.

Background: The QRS prolongation and its relation to malignant ventricular arrhythmias are topics of interest. Controversies exist about the methodology of measuring the QRS. The aim of this study was to assess the accuracy and reproducibility of manual measurement of the QRS in standard electrocardiograms in patients with right bundle branch block and compare results with computer reading., Methods and Results: Five experienced cardiologists at different levels of training were required to measure QRS duration in 30 electrocardiograms with different degrees of right bundle branch block collected from 24 randomly selected patients who had had radical repairs of tetralogy of Fallot. In each set of electrocardiograms there were six records which had been duplicated. The observers were neither told the purpose of the study nor how the electrocardiograms had been obtained, nor informed that some of the electrocardiograms were duplicates. Photocopies were identified by number, covering the patient's name and computerised measurement. Significant differences were found in the measurement of QRS in the same ECG calculated twice by the same observer (with an absolute variation up to 50 ms), within different observers (P=0.037) and measured manually or by computer (P=0.019). The width of the QRS did not influence the measurements as the biggest intra-observer variation (50 ms) was observed for relatively wide complex (median value between the two measurements 155 ms) and the biggest inter-observer (60 ms) for narrow complex (median value between the five measurements 110 ms). The QRS morphology appeared to influence the measurements, as the intra- and inter-observer variations were more consistent in the presence of obvious notching, slurrings and terminal slow vectors., Conclusions: Measurement of QRS is difficult, can be operator dependent and influenced by the presence of conduction abnormalities which reduce its accuracy and reproducibility.

The perioperative factors potentially associated with post-coronary artery bypass grafting (CABG) ventricular tachyarrhythmias (VT) onset have not been deeply investigated. Monomorphic or polymorphic ventricular tachycardia and ventricular fibrillation represent the most dreadful arrhythmic events that can complicate the postoperative course of CABG. As a consequence, the aim of our paper was to identify which perioperative variables might predict post-CABG VT occurrence. One hundred and fifty-two consecutive patients who underwent CABG surgery at our Institution were included in the study. Post-CABG VT occurred in 13 out of 152 patients (8.5%, six cases of monomorphic ventricular tachycardia and seven cases of ventricular fibrillation). At univariate analysis, VT patients were significantly younger (54.8+/-6.6 vs. 60.1+/-8.8, P=0.038), exhibited a more severe coronary artery disease (CAD) (number of diseased vessels 2.92+/-0.3 vs. 2.45+/-0.7, P=0.023, and percentage of patients with three-vessel CAD 91.7% vs. 57.3%, P=0.043) and received a greater number of CABGs than those remaining in sinus rhythm (SR) (percentage of patients receiving three or more CABGs 76. 9% vs. 38.8%, P1000 76.9% vs. 38%, Pnormal range 72.7% vs. 30.7%, P=0.014), electrolyte derangement (84.6% vs. 45.6%, P=0.017) and a severe haemodynamic impairment (need for IABP 23% vs. 2.9%, P1000, postoperative electrolyte imbalance, the need for three or more CABGs and of IABP all were independent correlates for VT. In conclusion, post-CABG VT seem to be related to the preexistence of a severe underlying coronary artery disease along with perioperative triggering factors such as acute ischemia, electrolytic disorders and a sudden haemodynamic impairment.

Objective: To assess the effects of treatment with verapamil on regional and global left ventricular (LV) diastolic function in paediatric patients with hypertrophic cardiomyopathy (HCM)., Design: Twelve patients (age range 5.1 to 12.3 years, median 8.6) with HCM were evaluated during ongoing chronic oral treatment with verapamil (4 mg/kg/day) and four days after withdrawal of therapy. Twelve age- and body surface area-matched normal children served as controls. In an echocardiographic study, global LV diastolic function was evaluated by assessing isovolumic relaxation time (IVRT) and mitral flow indexes, including peak filling rate normalized to mitral stroke volume (PFR/SV). In addition, regional LV diastolic function was assessed by pulsed-wave Doppler tissue imaging at the subendocardial portion of the middle region of the anterior and posterior interventricular septum, and anterolateral and inferior walls to measure the peak velocities and the velocity-time integrals of myocardial excursion in both early diastole and atrial systole. In addition, as an index of diastolic asynchrony (AsyI), the variation in time to peak filling rate, measured as the time from the peak of the R wave on the electrocardiogram to the peak of the regional E wave, among the four myocardial regions was defined by subtracting the smallest value from the greatest and expressing the difference as a percentage of the smallest value., Results: Compared with the controls, patients with HCM without therapy showed a longer IVRT (P<0.01) and a decrease in PFR/SV (P<0.01) without a compensatory increase in filling during atrial systole. Oral administration of verapamil induced a significant shortening of the IVRT (P=0.003) and an increase in PFR/SV (P=0.02). Furthermore, patients with HCM without therapy showed a significantly longer time to peak filling rate (P<0.01) associated with a decreased peak velocity in early diastole without a concomitant increase in peak velocity during atrial systole in each of the myocardial regions. Furthermore, the AsyI was higher in the HCM group than in controls (19% versus 6%, respectively), and this index was inversely correlated with the PFR/SV (r=-0.86, P<0.001). The regional diastolic velocity of the myocardium at each of the four analyzed regions was not significantly different with verapamil, but the AsyI was significantly lower (P<0.05)., Conclusions: Children with HCM show abnormalities of both global and regional LV diastolic function. In these patients, chronic administration of verapamil plays a crucial role in the improvement in global LV filling and, as a consequence, in clinical manifestations. The beneficial effects of verapamil seem to be related to a reduction in diastolic asynchrony more than to significant changes in diastolic velocities of the myocardial fibres.

Ventricular repolarization analysis has been shown to be effective in the identification of electrical myocardial instability leading to ventricular arrhythmias. The aim of the present study was to examine ventricular repolarization time indexes, in terms of both absolute measures and dispersion across the myocardium, in young patients with repaired tetralogy of Fallot (41 pts; 28M/13F, age 11.7+/-3.6 years), assessing, furthermore, the possible influence of known negative prognostic factors relative to the surgical operation and residual haemodynamic abnormalities. The data of the study group were compared with those of 33 aged-matched asymptomatic control subjects (22M/11F, age 11.7+/-2.3 years). Ventricular depolarisation, as expressed by QRS duration, resulted significantly longer in total Fallot group than in the Control group (P<0.0001). Particularly, patients operated through a right ventricular approach showed higher values of QRS interval (P<0.0001) than those operated through a combined transatrial-transpulmonary approach. All the patients operated on for tetralogy of Fallot exhibit, with respect to control subjects, an inhomogeneous prolongation of ventricular repolarization across the myocardium, as showed by the significant increase in the absolute indexes of ventricular repolarization, JTc (P<0.001), QT (P<0.0001) and QTc (P<0.0001) with a concomitant prolongation of the indexes of dispersion of ventricular recovery time, QTcD (P<0.0001), JTcD (P<0.0001), 'adjusted' QTcD (P<0.001) and Tp-Te interval (P<0.0001). A temporal and regional variation in the ventricular repolarization across the myocardium in patients with repaired tetralogy of Fallot, could create the pathophysiological substrate for an increased cardiac electrical instability. The presence of negative prognostic factors, relative to the surgical intervention or residual haemodynamic abnormalities, even if not influencing the arrhythmic substrate, invariably present, could determine 'trigger' conditions essential for the development of ventricular arrhythmias.

Study Population: Twenty patients without laboratory evidence of cardiac disease who underwent electrophysiological study because of recurrent ventricular tachyarrhythmias., Patients and Methods: The study population was divided into two groups: group A (20 patients [six males and 14 females] mean age 42.2 +/- 13 years), with idiopathic ventricular tachycardia (VT), and group B (30 controls [10 males and 20 females] mean age 43.6 +/- 16 years). Noninvasive multiparametric analysis of the ventricular repolarization phase was performed on the standard 12-lead electrocardiogram by using a digitizer connected with a computerized system. The intervals JT, heart rate-corrected JT (JTc), JT apex (JTa), heart rate-corrected JTa (JTac), T apex T end (TaTe) and heart rate-corrected TaTe (TaTec) were measured and considered to be representative of the whole depolarization process. QT dispersions (QTeD) and QTc dispersions (QTecD) were calculated to assess the degree of spatial inhomogeneity of action potential duration., Results: Patients in group A had higher JT (272 +/- 36 ms versus 265 +/- 25 ms, P = 0.01), JTc (336 +/- 28 ms versus 318 +/- 18 ms, P = 0.01), JTa (210 +/- 28 ms versus 185 +/- 28 ms, P = 0.001) and JTac (240 +/- 20 ms versus 215 +/- 13 ms, P < 0.001) values than those of patients in group B, despite shorter TaTe (71 +/- 10 ms versus 90 +/- 18 ms, P < 0.001) and TaTec (88 +/- 12 ms versus 110 +/- 12 ms, P < 0.001). Moreover, QTeD and QTecD were significantly longer in group A than in group B (55 +/- 18 ms versus 42 +/- 19 ms [P = 0.01] and 80 +/- 18 ms versus 55 +/- 28 ms [P = 0.001], respectively)., Conclusions: Patients with idiopathic VT exhibit inhomogeneous prolongation of ventricular repolarization, due to a considerable increase in the initial part in association with a shorter terminal phase, as well as a greater dispersion of ventricular repolarization.

Atrial fibrillation is the most common cardiac rhythm disorder associated with hospitalization. Two therapeutic options have been available: antiarrhythmic drug therapy, and external or internal electrical cardioversion. Electrical cardioversion of atrial fibrillation remains one of the most widely used and effective treatments for the restoration of normal sinus rhythm. However, many patients continue to receive an antiarrhythmic drug before and after cardioversion in an attempt either to cardiovert the arrhythmia chemically or to maintain sinus rhythm after successful cardioversion. Because some pharmacological agents can affect the cardioversion procedure for atrial fibrillation or flutter, and because many patients with such arrhythmias may require electrical cardioversion when they are taking antiarrhythmic drugs, the question of a possible effect of drug therapy on the efficacy and safety of electrical cardioversion of atrial fibrillation arises. Early reports of direct current cardioversion provoking potentially lethal ventricular arrhythmias raised suspicions of an arrhythmogenic role for digoxin antiarrhythmic therapy, and it is customary to withhold these drugs for 24 to 48 h before cardioversion is attempted. However, this complication is likely to arise only in patients who are close to, or actually manifesting, signs of drug toxicity. On the other hand, treatment with therapeutic concentrations of antiarrhythmic drugs before cardioversion may in some cases be associated with a significant reduction in the number of shocks and decreased energy required to restore sinus rhythm, a lower incidence of postshock arrhythmias and a reduced risk of early recurrence of atrial fibrillation.

Antiarrhythmic drugs are known to affect the depolarization and repolarization time in a different fashion. The aim of the present study was to compare the effects of Sotalol, Flecainide and Propafenone on some common (QT, QTc, JT, JTc) or uncommon (QTc dispersion, T-peak to T-end interval) electrocardiographic parameters in order to evaluate the effects of these antiarrhythmic drugs on ventricular repolarization time both in terms of absolute values and of dispersion across the myocardium. The analysis of these antiarrhythmic drug effects was performed on the standard 12-lead electrocardiograms of 31 patients (17F and 14M, age 38.1+/-17 years, range 11-67 years) in the free-drug state and at the steady state after oral treatment with Sotalol (160 mg daily), Flecainide (200 mg daily) and Propafenone (450 mg daily). These drugs were prescribed, separately, to all the 31 patients, free of underlying structural heart disease, for the treatment of their atrio-ventricular nodal re-entry tachycardia. Data of the present study show that Sotalol, over the range prescribed, significantly prolongs ventricular repolarization index QT (P=0.001), JT (P=0.0001) and JTc (P=0.0001) values in an homogeneous fashion, as shown by the significant decrease in QTcD (P=0.019) and Tp-Te (P=0.01). On the contrary, Flecainide treatment was associated with an increase in QTcD (P=0.029), Tp-Te (0.0001), QT (P=0.001), QTc (P=0.0001) and QRS (P=0.0001), with no significant changes in JT and JTc. Propafenone, over the range prescribed, did not affect repolarization time, resulting only in a prolongation of depolarization time as expressed by the increase of QRS (P=0.0001).

The aim of our study was to analyze the ventricular repolarization phase in patients with isolated aortic stenosis (AS) in order to search for possible abnormalities that might contribute to an explanation of the electrical instability peculiar to this valve disease. We selected a population of 39 patients with isolated AS (25 M and 14 F, mean age 60+/-16 yrs). As controls we considered a group of 31 age-matched healthy subjects 20 M and 11 F, mean age 55+/-14 yrs, P=NS. Disease severity was assessed by echocardiography, calculating the maximum and mean pressure gradients max and mean PG) and the functional valve orifice area. Various electrocardiographic intervals (QT, QT'c, JT, JTc) and indices (QT and QTc dispersion were adopted for a detailed non-invasive evaluation of the ventricular repolarization. In patients with AS, M-QT (391+/-45 ms vs 362+/-25 ms, P=0.002), M=QTc (431+/-29 ms vs 412+/-19 ms, P=0.003), M-JT (290+/-41 ms vs 265+/-26 ms, P=0.003, M-JTc 331+/-29 ms vs 302+/-19 ms, P<0.001, QTD (67+/-34 ms vs 40+/-15 ms, P<0.001), QTcD (77+/-36 ms vs 52+/-23 ms, P<0.001) all resulted significantly greater than in controls. QTD and QTcD both resulted linearly related either to max PCi (r=0.388, P=0.018 and r=0.357, P=0.03) or to mean PG (r=0.513, P=0.004 and r=0.438, P=0.015), while M-JT and M-JTc turned out to be directly related only to mean PG (r=0.436, P=0.016 and r=0.483, P=0.007). Our findings suggest a prolonged duration of ventricular recovery and a greater dispersion of ventricular repolarization in patients with AS and might account for the electrical instability proper to this valve dysfunction. Besides, the existence of a linear direct relation between the severity of AS and the degree of inhomogeneity of left ventricular recovery, together with the correlation found among mean PCr and the total duration of the repolarization phase, expressed by the intervals JT and JTc, strongly suggest the hypothesis that in AS arrhythmogenic substrates development parallels the worsening of the valve defect.

Patients with dilated cardiomyopathy, ventricular volume or pressure overload, or dysynergistic ventricular contraction and relaxation are prone to develop severe ventricular arrhythmias. In these patients it has been suggested that the abnormal mechanics of contraction can disturb 'mechano-electric feedback', also known as 'contraction-excitation feedback', which is defined as the development of electrophysiological changes during or after changes in mechanical loading. This electrical instability, expressed by significant changes in ventricular repolarization and refractoriness and by the development of afterdepolarizations, has been variously reported in isolated tissues and isolated ventricles as well as in hearts in vivo. Furthermore, it is known that many patients with supraventricular tachycardia but otherwise structurally normal hearts can develop atrial fibrillation and that atrial arrhythmias frequently occur in the setting of acute or chronic increases in atrial size and pressure. It is possible that changes in atrial load directly alter the electrophysiological properties of the atrium by an analogue mechanism of contraction-excitation feedback. This paper reviews the literature concerning mechanoelectric feedback involvement in rhythm disorders, with the aim of investigating, through basic and clinical research, the clinical and therapeutic implications.

We evaluated the arrhythmic profile in a population of 20 Becker muscular dystrophy (BMD) patients searching for possible correlations between the severity of the arrhythmic events, the cardiac autonomic balance (assessed by heart rate variability analysis in the time domain) and the degree of left ventricular systolic impairment. A population of 14 male healthy individuals served as the control group. BMD subjects exhibited lower values of SDNN (P=0.013), SDANN index (P=0.008) and 24-h mean heart rate (P=0.002). The total number of premature ventricular beats (totPVB) and the number of PVB out of 1000 heartbeats (PVB/1000) appeared also higher in BMD subjects (P=0.05 and P=0.046, respectively). No difference was found in terms of 24-h mean QTc and 24-h longest QT among the two groups. TotPVB and PVB/1000 were inversely related to both the ejection fraction (r= -0.620, P=0.004 and r= -0.517, P=0.019) and to the shortening fraction (r= -0.568, P=0.009 and r= -0.469, P=0.037). Twenty-four-h mean QTc was also inversely related to both the ejection fraction (r= -0.520, P=0.019) and the fractional shortening (r= -0.491, P=0.028). These data suggest that in BMD there is cardiac autonomic imbalance characterized by sympathetic predominance and an increased susceptibility to ventricular arrhythmias, even in the absence of overt cardiomyopathy. Furthermore, the severity of the arrhythmic profile in BMD appears closely related to the degree of left ventricular systolic dysfunction.

Cardiac arrhythmias are common in patients with respiratory failure from chronic obstructive pulmonary disease (COPD). Several factors may be potentially arrhythmogenic in these patients, including hypoxemia and hypercapnia, acid-base disturbances, cor pulmonale and the use of digitalis, methylxanthines, and sympathomimetic drugs. The aim of this study was to examine the effect of hypoxemia and hypercapnia on QTc dispersion (QTcD) in COPD patients, and to evaluate the effect of a partial correction of one of these pro-arrhythmic factors, the hypoxemia, on Qtc dispersion, as QTcD has been proposed as a marker of heterogeneous repolarization and, hence of ventricular electrical instability. We showed that in 15 hypoxemic/hypercapnic COPD patients, compared to 20 controls, the QTcD was significantly higher (49.7 +/- 10.6 vs. 22.9 +/- 9.8 ms; P = 0.0001); furthermore, after only 24 h of oxygen therapy, and hence after a partial correction of hypoxemia, there was a significant reduction in QTcD in COPD patients (49.7 +/- 10.6 vs. 36.3 +/- 10.1 ms; P = 0.018). The data of the present study suggest that the increase in QTcD may be an early marker of a blood gas mediated electropathy in COPD patients.

The aim of our study was to assess whether the presence of ventricular preexcitation affects the spatial distribution of ventricular recovery time. Recent reports support the hypothesis that QT and QTc dispersions (QTd and QTcd) can be reliably adopted as a non-invasive parameter to estimate regional discrepancies of ventricular repolarization. The ECGs of 32 healthy subjects with Wolff-Parkinson-White syndrome and of 29 normal individuals have been analysed using a Digitizer (Calcomp 9000), in order to obtain, for each subject, a mean QRS (M-QRS), QT (M-QTe), QTc (M-QTec), JT (M-JT), JTc (M-JTc) from all the measured intervals of the 12 standard ECG leads. QRS, QT and QTc dispersions (QRSd, QTd, QTcd) were defined as the difference between the maximal and minimal QRS, QTe and Qtec values calculated in the various leads. We attained the following results: patients with WPW syndrome exhibited, with respect to controls, longer M-QRS (P < 0.001) and M-QTec (P < 0.001) values, despite similar M-QTe (P = NS), M-JT (P = NS) and M-JTc (P = NS). QRSd did not differ in the two groups(P = NS), while QTd and QTcd both resulted significantly greater in pre-excited subjects (P < 0.001). In the WPW group, QRSd was not related either to QTd (r = 0.325, P = NS) or to QTcd (r = 0.148, P = NS), while in the controls there was a significant relation between QRSd and both QTd (r = 0.522, P = 0.004) and QTcd (r = 0.379, P = 0.042). Our findings suggest that the presence of ventricular pre-excitation does not determine a prolongation of the mean ventricular recovery time, but increases regional discrepancies of the re-polarization process. This assumption is supported by the observation of greater values of QTd and QTcd associated with a similar QRSd.

QTc interval dispersion (QTcd) analysis (difference between maximum and minimum QTc calculated from at least five of the standard 12 ECG leads) and signal-averaged electrocardiograms were performed on 23 patients referred to our coronary care unit because of acute myocardial infarction. Late potentials were considered positive if all three of the following criteria were satisfied: (1) total QRS duration (QRSd) > 114 ms; (2) duration of QRS under 40 muV (LAS 40) > 38 ms; (3) root mean square voltage of the last 40 ms of QRS (RMS 40) < 25 muV. Patients were divided into two groups according to the presence (group A, 9 patients) or absence of late potentials (group B, 14 patients). Group A patients showed a significantly higher QTcd (0.0652 +/- 0.0177 s vs. 0.0448 +/- 0.0201 s; P = 0.021) and a significantly longer mean QTcm (0.43117 +/- 0.01817 s vs. 0.40472 +/- 0.03013 s; P = 0.028) than group B patients. Among the three different parameters used to define the presence of late potentials, QTcd was significantly related to LAS 40 (r = 0.418, P = 0.047) and mean QT cm to QRSd (r = 0.497; P = 0.016). We also found a significant correlation between QTcd and mean QTcm (r = 0.426; P = 0.043). In conclusion, our data suggest that (1) the presence of late potentials is associated with a greater dishomogeneity of ventricular recovery time; (2) the longer the duration of late potentials, expressed by LAS 40, the greater the QTcd, suggesting that the dispersion of repolarization could be attributed to slowly conducting areas from which late potentials arise; (3) mean QTcm is not useful to identify these areas because it is more affected by total rather than by terminal QRS duration; (4) regional discrepancies of ventricular recovery time are connected with general repolarization duration.