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Backgrounds: It's still unclear if different patterns of intraventricular flow dynamics may be detected in patients nonresponders to cardiac resynchronization therapy (CRT) as compared to responders ones. Aim of this study was to evaluate the characteristics of left ventricular (LV) flow dynamics 6-months after CRT to identify Echo-particle imaging velocity (PIV) patterns were more frequently detected in nonresponders patients., Methods: Thirty-two patients with dilated cardiomyopathy, undergoing CRT, were enrolled in this study. All patients underwent 2D and 3D echo and fluid dynamics assessment 6 months after CRT, during active CRT (CRT-ON) and during a temporarily discontinued state (CRT-OFF). LV volumes systolic and diastolic volumes (LVESV and LVEDV), ejection fraction (LVEF), global longitudinal strain (GLS), systolic dyssynchrony index (SDI), and several geometrical and functional Echo-PIV-derived parameters were calculated. Patients were divided in two groups: "responders" to CRT (decrease in LVESV>15% 6 months after CRT) and "nonresponders.", Results: During CRT-OFF, LVEF, GLS were lower, while SDI and LVESV were higher in nonresponders group (P=.030, P=.051, P=.035, and P=.025, respectively). Energy dissipation, vortex area, and vorticity fluctuation were higher in "nonresponders" patients during CRT-OFF (P=.038, P=.054, and P=.035, respectively). During CRT-ON, energy dissipation, vortex area, and vorticity fluctuation further increase in nonresponders patients (P=.020, P=.038, and P=.030, respectively) with a concomitant worsening of SDI (P=.045)., Conclusion: Our data show a significant worsening in flow-derived parameters in CRT "nonresponders" patients as compared with responders. Further larger longitudinal studies are necessary to assess whether these more chaotic intraventricular flow-patterns may contribute to a persistent adverse remodeling observed in this subset of patients., (© 2017, Wiley Periodicals, Inc.)

Background: Previous studies evaluating the progression of the necrotic wave in relation to heart rate were carried out only in animal models of ST-elevated myocardial infarction (STEMI). Aim of the study was to investigate changes of myocardial salvage in relation to different heart rates at hospital admission in timely reperfused patients with STEMI by using cardiovascular magnetic resonance (CMR)., Methods: One hundred-eighty-seven patients with STEMI successfully and timely treated with primary coronary angioplasty underwent CMR five days after hospital admission. According to the heart rate at presentation, patients were subcategorized into 5 quintiles: <55 bpm (group I, n = 44), 55-64 bpm (group II, n = 35), 65-74 bpm (group III, n = 35), 75-84 bpm (group IV, n = 37), ≥85 bpm (group V, n = 36). Area at risk, infarct size, microvascular obstruction (MVO) and myocardium salvaged index (MSI) were assessed by CMR using standard sequences., Results: Lower heart rates at presentation were associated with a bigger amount of myocardial salvage after reperfusion. MSI progressively decreased as the heart rates increased (0.54 group I, 0.46 group II, 0.38 group III, 0.34 group IV, 0.32 group V, p<0.001). Stepwise multivariable analysis showed heart rate, peak troponin and the presence of MVO were independent predictor of myocardial salvage. No changes related to heart rate were observed in relation to area at risk and infarct size., Conclusions: High heart rates registered before performing coronary angioplasty in timely reperfused patients with STEMI are associated with a reduction in salvaged myocardium. In particular, salvaged myocardium significantly reduced when heart rate at presentation is ≥85 bpm.

Objectives: The aim of this study was to determine the prevalence of right intraventricular dyssynchrony, its determinants and prognostic impact in idiopathic, heritable, and anorexigen-induced pulmonary arterial hypertension., Background: Right ventricular dyssynchrony has been described in pulmonary arterial hypertension, but no evidence is available on its prognostic impact and evolution after therapy., Methods: In 83 consecutive therapy-naïve patients, right ventricular dyssynchrony was evaluated by 2-dimensional speckle-tracking echocardiography calculating the standard deviation of the times to peak-systolic strain for the 4 mid-basal right ventricular segments (RV-SD4). After baseline (World Health Organization [WHO] class, pulmonary hemodynamics, 6-min walk test [6 MWT]), a second assessment was performed after 12 months or when clinical worsening occurred., Results: Patients with right ventricular dyssynchrony (RV-SD4 >18 ms) had advanced WHO class, worse 6 MWT, right ventricular remodeling, and hemodynamic profile compared with patients ≤ 18 ms. Determinants of dyssynchrony included pulmonary vascular resistance, QRS duration, and right ventricular end-diastolic area (r(2) = 0.38; p < 0.000001). At 12 months, 32.5% of patients presented clinical worsening (actuarial rates: 19% at 6 months, 31% at 1 year). Multivariable models for clinical worsening prediction showed that the addition of RV-SD4 to clinical and hemodynamic variables (WHO IV, 6 MWT, and cardiac index) significantly increased the prognostic power of the model (0.74 vs. 0.81; p = 0.005, 95% confidence interval [CI]: 0.02 to 0.11). Receiver operating characteristic analysis identified RV-SD4 ≥ 23 ms as the best cutoff value for clinical worsening prediction (95% negative predictive value). At 12 months, normalization of dyssynchrony was achieved in patients with a large reduction of pulmonary vascular resistance (-42 ± 4%)., Conclusions: Right ventricular dyssynchrony is frequent in pulmonary arterial hypertension, is an independent predictor of clinical worsening, and might regress during effective treatments., (Copyright © 2015 American College of Cardiology Foundation. Published by Elsevier Inc. All rights reserved.)

Aims: Left ventricular (LV) diastolic filling is characterized by the formation of a vortex that supports an efficient transit into systolic ejection. Aim of this study was to assess the intraventricular (IV) blood flow dynamics among patients with ST elevated myocardial infarction (STEMI) at different degrees of LV dysfunction, in the attempt to find novel indicators of LV pump efficiency., Methods and Results: Sixty-four subjects, 34 consecutive STEMI patients and 30 healthy controls, underwent before hospital discharge 2D speckle tracking echocardiography to assess global longitudinal strain (GLS), and echo-particle image velocimetry analysis to assess flow energetic parameters. Left ventricular volumes ejection fraction (LVEF) and global wall motion score index (GWMSI) were evaluated by 3D echocardiography. ST elevated myocardial infarction patients were subdivided into three groups according to LVEF. Energy dissipation, vorticity fluctuation, and kinetic energy fluctuation indexes, which characterize the degree of disturbance in the flow, exhibit a biphasic behaviour in STEMI patients when compared with controls, with the highest values in patients with still preserved LV function and progressive lower values with LV function worsening. Significant linear correlations were found between energy dissipation index and both LVEF and GLS (r = 0.57, P < 0.001 and r = -0.61, P = 0.001, respectively). Kinetic energy fluctuation index significantly correlates with both LVEF (r = 0.75, P < 0.001) and GLS (-0.58, P = 0.002). Finally, a significant correlation was observed between GWMSI and energy dissipation index (-0.56, P = 0.008)., Conclusions: The present study describes, for the first time, the progression of IV flow energetic properties in patients with acute myocardial infarction at different stages of LV dysfunction when compared with healthy controls. Further data are needed to assess the role of these parameters in the development and maintenance of LV dysfunction., (Published on behalf of the European Society of Cardiology. All rights reserved. © The Author 2014. For permissions please email: journals.permissions@oup.com.)

Aims: Global and regional longitudinal strain (GLS-RLS) assessed by two-dimensional speckle tracking echocardiography (2D-STE) are considered reliable indexes of left-ventricular (LV) function and myocardial viability in chronic ischaemic patients when compared with delayed-enhanced cardiac magnetic resonance (DE-CMR). In the present study, we tested whether GLS and RLS could also identify early myocardial dysfunction and transmural extent of myocardial scar in patients with acute ST elevation myocardial infarction (STEMI) and relatively preserved LV function., Methods and Results: Twenty STEMI patients with LVEF ≥40%, treated with PPCI within 6 h from symptoms onset, underwent DE-CMR and 2D-echocardiography for 2D-STE analysis 6 ± 2 days after STEMI. Wall motion score index (WMSI) and LV ejection fraction (LVEF) were calculated by both methods. Infarct size and transmural extent of necrosis were assessed by CMR. GLS and RLS were obtained by 2D-STE. Mean GLS of the study population was -14 ± 3.3, showing a significant correlation with both LVEF and WMSI, by CMR (r = -0.86, P = 0.001, and r = 0.80, P = 0.001, respectively) and time-to-PCI (r = 0.66, P = 0.038). A weaker correlation was found between GLS and LVEF and WMSI assessed by 2D-echo (r = -0.65, P = 0.001, and r = 0.53, P = 0.013, respectively). RLS was significantly lower in DE-segments when compared with normal myocardium (P < 0.0001). A cut-off value of RLS of -12.3% by receiver-operating characteristic (ROC) curves identified DE-segments (sensitivity 82%, specificity 78%), whereas a cut-off value of -11.5% identified transmural extent of DE (sensitivity 75%, specificity 78%)., Conclusion: Our findings indicate that RLS and GLS evaluation provides an accurate assessment of global myocardial function and of the presence of segments with transmural extent of necrosis, with several potential clinical implications.

Objectives: To address if baseline endothelin-1 (ET-1) plasma levels might predict clinical worsening (CW) in patients with idiopathic pulmonary hypertension (IPAH) treated with bosentan., Methods: Forty-four consecutive patients with IPAH (WHO classes II-III) were included in this study. After an initial assessment (clinical status, pulmonary hemodynamics, samples for adrenomedullin (ADM), ET-1 and brain natriuretic peptide (BNP) plasma levels), patients were treated with bosentan and followed-up for CW., Results: We observed CW in 24 patients. Actuarial rates of freedom from CW were 74% at 1 year, 56% at 2 years, and 43% at 3 years. Patients with CW had a worse WHO functional class (II/III; no-CW 14/6 vs CW 5/19, p=0.002), six-minute walk-test distance (no-CW 439+94 m vs CW 385+82 m, p=0.04), mean pulmonary artery pressure (no-CW 47.4+10.6mm Hg vs CW 56+12.6mm Hg, p=0.02) and pulmonary vascular resistance (PVR no-CW 12.5+4.8 WU vs CW 16.4+6.3 WU, p=0.03) than the no-CW group. Moreover ET-1 (no-CW 14.1+4.2 pg/ml vs CW 21.3+6.3 pg/ml, p=0.0001), ADM (no-CW 14.9+7 pg/ml vs CW 21.5+10.4 pg/ml p=0.002) and BNP (no-CW 82.8+35.3 pg/ml vs CW 115.4+39.6 pg/ml, p=0.007) plasma levels were significantly higher in the CW group than in the no-CW group. The multivariate Cox proportional hazards model identified WHO class III (RR 4.6, 95%CI 14.6-1.45), ET-1 plasma levels (RR 1.1, 95%CI 2.05-1.01) and PVR (RR 1.2, 95%CI 1.3-1.03) as independent risk factors for CW., Conclusions: These data confirm the high rate of CW in patients with IPAH treated with bosentan and document the impact of the endothelin system on CW of these patients., (Copyright © 2011. Published by Elsevier Ireland Ltd.)

Background: Oral drugs have made the treatment of pulmonary hypertension (PH) feasible in non-expert centers, which could delay patient access to prostanoid therapy., Methods: Fifty-seven consecutive patients with precapillary PH received a prostanoid in our center. Data at prostanoid initiation included modality of center referral, medical history, New York Heart Association [NYHA] class, exercise capacity, echocardiographic parameters, and hemodynamics., Results: Overall survival at 1, 2, and 3 years was 85%, 69%, 55%, respectively. Non-survivors had worse NYHA class III/IV (17/12) than survivors (27/1; p < 0.01) and exercise capacity on 6-minute-walk distance (254 ± 114 vs 354 ± 91 meters; p < 0.01). Non-survivors were more frequently referred on oral therapy (83% vs 36%; p < 0.01) and had a higher rate of urgent prostanoid treatment (69% vs 17%; p < 0.0001). Multivariate analysis (hazard ratio [95% confidence interval]) found the independent prognostic factors were urgent prostanoid therapy (2.0 [1.1-3.9]) and NYHA class (3.5 [1.5-8.2]). Survivors had a significant response to prostanoid, improving NYHA class from 2.8 ± 0.4 to 2.3 ± 0.5 (p = 0.002), 6-minute walk distance from 354 ± 91 to 426 ± 82 meters (p = 0.0001), and pulmonary hemodynamics (pulmonary artery pressure from 56 ± 13 to 44 ± 18 mm Hg [p < 0.05]; cardiac index from 2.0 ± 1.2 to 3.1 ± 1.2 liters/min/m(2) [p = 0.002], and pulmonary vascular resistance from 17 ± 10 to 8 ± 6 WU [p = 0.001])., Conclusions: Referral of patients on oral treatment to a tertiary PH center is delayed and significantly affects prognosis., (Copyright © 2012 International Society for Heart and Lung Transplantation. Published by Elsevier Inc. All rights reserved.)

The purpose of this study was to evaluate post-marketing efficacy and safety data for therapy with daptomycin (DAP) in Italy. Data from patients treated with DAP at 30 centres between January 2006 and July 2009 were analysed according to the protocol of the EU-CORE(SM). In 359 patients, DAP was most commonly prescribed for skin and skin-structure infections (55%), infective endocarditis (13%), and bacteraemia (12.5%). DAP was associated with rapid improvement, and clinical success rates ranging from 77 to 91%, despite almost half of the patient population being ≥65 years of age, 86% having significant underlying disease, and many being affected by drug-resistant pathogens. Staphylococcus aureus represented 35% of all pathogens isolated. Success rates for all staphylococcal and enterococcal infections were >80%, including methicillin-resistant S. aureus (MRSA) and methicillin-susceptible S. aureus (MSSA). Clinical outcomes were similar for DAP whether used as first- or second-line therapy. DAP was well tolerated even with prolonged treatment.

Aim: To study the role of endothelin (ET-1) and adrenomedullin (AM) on pulmonary vascular pressure/flow characteristic (pulmonary arterial pressure/cardiac output (Pap/CO)) during low-dose dobutamine infusion., Methods: Case control study of 14 patients (12 men, 2 women) with severe lung disease (chronic obstructive pulmonary disease, COPD n=5; cystic fibrosis, CF n=9) and 5 control subjects (CTRL, 4 men, 1 woman). ET-1 and AM plasma levels in pulmonary artery (mixed venous blood, ven) and aorta or femoral artery (arterial, art), were measured at baseline and during dobutamine infusion (5-10-15 mcg kg(-1) min(-1)). The Ppa/CO coordinates obtained at baseline and during dobutamina infusion for each patients were used to calculate the Slope and Intercept by linear regression analysis., Results: Baseline hemodynamics measurements were similar in the three groups with a trend towards a mild elevation in Ppa in CF group (Ppa mm Hg: CTRL 19+/-3.5, COPD 19.4+/-5.5, CF 22.7+/-7.5). Baseline plasma ET-1(ET-1ven pg ml(-1): CTRL 13.9+/-6.7, COPD 20.1+/-14, CF 20.4+/-7.1; ET-1art pg ml(-1): CTRL 16.7+/-6.4, COPD 20.1+/-11.7, CF 18.1+/-3.9) and AM (AMven pg ml(-1): CTRL 15.8+/-5, COPD 31.8+/-17.6, CF 27.7+/-7.6; AMart pg ml(-1): CTRL 15.9+/-1.4, COPD 21.4+/-3.8, CF 27+/-7.6) showed a trend towards higher value among patients' groups compared to the controls. Baseline ET-1 pulmonary gradient did not show significant difference among the three groups as well AM pulmonary gradient. Dobutamine infusion caused a comparable increase of heart rate and CO in the three groups. Mean pulmonary pressure had a trend towards a greater increase in COPD and CF than in controls, consequently, pulmonary Pap/CO relationship showed a steeper slope in patients' groups (Slope mm Hg L(-1) min(-1): CTRL 0.9+/-0.3, COPD 2.1+/-0.8 p<0.02 vs. CTRL, CF 1.9+/-0.9 p<0.03 vs CTRL). During dobutamine plasma ET-1 and AM showed a great individual variability resulting in no significant difference among groups. ET-1 pulmonary gradient showed a trend towards pulmonary uptake in patients' groups (ET-1art-ven pg min(-1): CTRL 2.7+/-2.9, COPD-6.1+/-7.8, CF -4+/-4.8) while AM pulmonary gradient did not show any particular pattern. During dobutamine ET-1 was significantly correlated to Pap/CO characteristics (Slope and ET-1ven, r=-0.59, p<0.05; Slope and ET-1art-ven, r=-0.60, p<0.05; Intercept and ET-1art-ven, r=0.63, p<0.004), and ET-1art-ven was the only independent variable related to Slope and Intercept., Conclusions: In patients with moderate pulmonary vascular impairment, ET-1 pulmonary gradient, but not AM pulmonary gradient, is inversely correlated with pulmonary incremental resistance, suggesting a role of ET-1 in the regulation of pulmonary vascular resistance.

Background: In diabetic patients, the combination of abciximab with stenting has been demonstrated to be the standard of care to reduce target vessel revascularization (TVR) and mortality. Moreover, a preprocedural hyperglycemia has been associated with a higher rate of TVR after an elective stent implantation. We sought to evaluate the effects of abciximab and/or preprocedural glycemic control on 30 and 180 days of TVR and on 1-year major adverse cardiac events (MACE-cardiac mortality, TVR, and myocardial infarction) in diabetic patients undergoing elective coronary stenting., Methods: From January 2002 through May 2003, diabetic patients undergoing elective stenting of de novo coronary artery lesions were randomized to abciximab or placebo infusion. Preprocedural hyperglycemia was defined as fasting plasma glucose >or=126 mg/dL (7.0 mmol/L) immediately before the procedure., Results: A total of 122 consecutive patients with diabetes (62.4 +/- 10.2 years, 80 men) were enrolled in the study. Sixty-nine (56.5%) were randomly assigned to receive abciximab (34 with and 35 without preprocedural hyperglycemia) and 53 (43.5%) to placebo (23 with and 30 without hyperglycemia). Target vessel revascularization was significantly lower in diabetic patients who received abciximab at 30 days (2.9% and 2.8% vs 8.7% and 6.6% in nonabciximab group with or without hyperglycemia, respectively, P < .01) but not at 6 months (31.4% and 26.5% vs 30% and 28.7%, P = NS). Conversely, the cumulative incidence of MACE was significantly higher among diabetic patients with preprocedural hyperglycemia (64.7% and 65.2%) versus diabetic patients with preprocedural glycemic control (37.1% and 40%), treated with or without abciximab, respectively (P < .05)., Conclusions: A preprocedural hyperglycemia is associated with a higher rate of MACE, regardless of the use of abciximab, in diabetic patients undergoing elective coronary stenting.

beta2-integrin subunit (CD18) plays an essential role in leukocyte recruitment and adhesion in sites of endothelial injury. We analyzed the surface expression of CD18 on T lymphocytes and monocytes in a series of patients presenting acute coronary syndrome (ACS) who underwent primary percutaneous intervention (PCI) for coronary artery revascularization. We found that basal CD18 expression on peripheral blood-derived CD4+ (but not CD8+) T lymphocytes was significantly increased in ACS patients as compared with age-matched healthy volunteers. During primary PCI, a significant increase in CD18 molecule density was detected immediately after balloon deflation (reperfusion) on both CD4+ T cells and monocytes obtained from the right atrium (RT) as compared with basal values. These data suggest that upregulation of CD18 molecules plays an important role in local recruitment of CD4+ T cells and monocytes to the site of endothelial damage after ischemia/reperfusion, therefore being responsible, at least in part, for the inflammatory-mediated complications associated with primary PCI.

Introduction: The use of low-dose dobutamine to maintain hemodynamic stability in pulmonary hypertension may have a detrimental effect on gas exchange. The aim of this study was to investigate whether inhaled nitric oxide (INO), dobutamine and a combination of the two have beneficial effects in patients with end-stage airway lung disease and pulmonary hypertension., Method: Hemodynamic evaluation was assessed 10 min after the administration of each drug and of their combination, in 28 candidates for lung transplantation., Results: Administration of INO caused a reduction in mean pulmonary arterial pressure (MPAP), an increase in PaO2 with a significant reduction in venous admixture effect (Qs/Qt).Dobutamine administration caused an increase in cardiac index and MPAP, with a decrease in PaO2 as a result of a higher Qs/Qt. Administration of a combination of the two drugs caused an increase in the cardiac index without MPAP modification and an increase in PaO2 and Qs/Qt., Conclusion: Dobutamine and INO have complementary effects on pulmonary circulation. Their association may be beneficial in the treatment of patients with mild to moderate pulmonary hypertension.

Preserved myocardial viability and recurrent symptomatic ischemia are the most widely accepted criteria indicating that coronary revascularization should take place in patients with postischemic left ventricular dysfunction. However, the presence of viable myocardium within the infarct zone does not necessarily imply recovery of function after coronary revascularization. The complex relation between the extent of transmural necrosis and the degree of residual perfusion within the infarct area plays an important role. However, independently of functional recovery, cell viability may have important clinical implications, since it may improve long-term prognosis by attenuating left ventricular remodeling processes. Several different methods are used to detect hibernating myocardium. Mounting evidence suggests that thallium-201 scintigraphy is most sensitive in identifying tissue viability, whereas dobutamine echocardiography is most specific in predicting functional recovery after revascularization. In between, myocardial contrast echocardiography is the only technique able to evaluate the microvascular integrity that is a condition sine qua non for both cell viability and later functional recovery. Combined information derived from these 3 different approaches might be considered as the best way to understand how the combination of contractile, viable but noncontractile, and dead tissue affect resultant function and prognosis.

Aims: The aim of this study was to analyse the relationship between infarct-related artery residual stenosis, assessed by quantitative coronary angiography, and left ventricular function changes during the in-hospital period in patients with acute myocardial infarction undergoing thrombolytic treatment., Methods and Results: The study population consisted of 90 patients with acute myocardial infarction treated with thrombolysis within 6 h of the onset of symptoms. Left ventricular function was serially assessed by an echocardiographic asynergy score (before thrombolysis and pre-discharge). Left ventricular end-diastolic and end-systolic volumes were also calculated. Coronary stenosis was evaluated by computer-assisted videodensitometric analysis at pre-discharge coronary angiography. Three subgroups were identified on the basis of left ventricular function changes: 25 patients (Group A) with regional myocardial improvement (echo score from 7.5 +/- 3.5 to 4.3 +/- 3.2), 51 (Group B) with no variation in echo score (4.8 +/- 2.7) and 14 (Group C) with myocardial regional worsening (echo score from 4.4 +/- 2.1 to 8.8 +/- 2.4). Group A patients exhibited a very high incidence of infarct-related artery patency (23/25 patients, 92%) vs 71% with unchanged (Group B) and 14% (Group C) with worsening regional left ventricular function (P < 0.001). Subdivision of the study population on the basis of residual stenosis severity showed that a significant improvement in left ventricular function was present only in the subgroup with residual stenosis < 75% (echo score from 5.2 +/- 3.4 to 3.6 +/- 2.9, P < 0.001)., Conclusion: These results support the important role exerted by complete coronary patency after thrombolysis in inducing left ventricular function recovery, and the poor functional improvement in patients with incomplete coronary patency.

Objectives: This study used myocardial contrast echocardiography to investigate the extent of residual perfusion within the infarct zone in a select group of patients with recently reperfused myocardial infarction and evaluated its influence on the ultimate infarct size., Background: Limited information is available on the status of myocardial perfusion within postischemic dysfunctional segments at predischarge and on its influence on late regional and global functional recovery., Methods: Twenty patients with acute myocardial infarction were selected for the study. Patients met the following inclusion criteria: 1) single-vessel coronary artery disease; 2) patency of infarct-related artery with persistent postischemic dysfunctional segments at predischarge; 3) stable clinical condition up to 6 months after hospital discharge. All selected patients underwent coronary angiography and myocardial contrast echocardiography before hospital discharge and repeated the echocardiographic examination 6 months later. Patients were grouped according to the pattern of contrast enhancement in predischarge dysfunctional segments., Results: In nine patients (group I), the length of segments showing abnormal contraction coincided with that of the contrast defect segments. In the remaining 11 patients (group II), postischemic dysfunctional segments were partly or completely reperfused. There was no difference between the two groups in asynergic segment length at predischarge (7.3 +/- 2.5 vs. 7.2 +/- 4.3 cm, p = NS). At follow-up study, asynergic segment length was significantly reduced in group II patients, whereas no changes were observed in group I patients (from 7.2 +/- 4.3 to 4.7 +/- 3.7 cm, p < 0.005; and from 7.3 +/- 2.5 to 7.5 +/- 2.9 cm, p = NS, respectively)., Conclusions: Among patients with a predischarge patent infarct-related artery, further improvement in regional and global function may be expected during follow-up when residual perfusion in the infarct zone is present.

The aim of this study was to examine whether myocardial contrast echocardiography (MCE) may be used to study regional myocardial blood flow distribution during dipyridamole-induced hyperemia. MCE was performed before and after dipyridamole infusion in 11 patients with a proximal, significant left anterior descending (LAD) coronary artery stenosis. The relation between contrast-derived parameters and the degree of coronary narrowing and the occurrence of transient regional wall motion abnormalities was also investigated. In the territory supplied by left circumflex coronary artery, mean peak contrast intensity increased after dipyridamole from 50 +/- 18 to 76 +/- 27 IU (p < 0.001). In contrast, a significant reduction in mean peak intensity was observed after dipyridamole in the LAD territory (from 41 +/- 27 to 13 +/- 13 IU, p < 0.01). Similar results were obtained with the use of the area under the time-intensity curve. An increase in peak intensity > or = 10 IU after dipyridamole administration separated normal regions from those supplied by a significant coronary artery lesion with a sensitivity of 91% and a specificity of 91%. Perfusion abnormalities were always detected by contrast echocardiography when septal motion abnormalities developed and, in five patients they were detected in the absence of clinical, electrocardiographic, and echocardiographic signs of ischemia. A weak correlation was found between both peak intensity and area under the curve and percent coronary diameter stenosis and cross-sectional area. In conclusion, dipyridamole MCE can be used during routine coronary angiography to assess myocardial blood flow distribution in patients with coronary artery disease.(ABSTRACT TRUNCATED AT 250 WORDS)

To determine the correlation of quantitative assessment of coronary narrowings with left ventricular functional impairment induced by exercise, 57 patients with 1-vessel coronary artery disease and without evidence of collateral flow were studied. A significant relation was observed between minimal cross-sectional area, percent area stenosis, minimal lumen diameter, percent diameter stenosis and the percentage of segmental area change from rest to peak exercise in a vascular distribution territory (r = 0.76, p less than 0.001; r = -0.55, p less than 0.001; r = 0.56, p less than 0.001; r = -0.75, p less than 0.001, respectively). For minimal cross-sectional area, the best cut-off value to separate significantly patients who had a decrease in contractility at peak exercise testing from those who had a normal response was 2 mm2 (p less than 0.001); for percent cross-sectional area stenosis, it was 75% (p less than 0.001); for minimal lumen diameter, it was 0.7 mm (p less than 0.001); and, for percent diameter stenosis, it was 85% (p less than 0.001). High cut-off values for angiographic variables are necessary to separate significantly patients who have a decrease in contractility at peak exercise testing from those who have a normal response. Several patients with mild coronary stenoses may have either normal or abnormal wall motion during exercise. Thus, exercise echocardiography is a useful tool in detecting the presence of fairly severe anatomic narrowing, whereas it is of limited clinical use in the assessment of intermediate coronary atherosclerotic lesions.

Two-dimensional and Doppler echocardiographic studies and a hemodynamic investigation were performed during dipyridamole testing in 42 subjects (13 control subjects and 29 patients with coronary artery disease [CAD]), to evaluate the ability of dipyridamole Doppler echocardiography in identifying patients with ischemic left ventricular dysfunction. In the control group, after dipyridamole infusion, Doppler-derived parameters increased significantly from baseline (p less than 0.001). In patients with CAD, peak flow velocity, flow velocity integral and stroke volume failed to increase after dipyridamole infusion (0.89 +/- 0.21 to 0.85 +/- 0.18 m/s, difference not significant; 14 +/- 3 to 12 +/- 4 cm, difference not significant, and 56 +/- 13 to 50 +/- 14 ml/beat, p less than 0.05, respectively). Heart rate, rate pressure product, systemic vascular resistance and mean right atrial pressure had similar variations in the 2 groups. Changes in the 3 Doppler-derived parameters are closely related to the variations of peak positive dP/dt, stroke volume (thermodilution) and left ventricular end-diastolic pressure and are closely related to the coronary angiography jeopardy score and to the appearance of wall motion abnormalities. Thus, by combining Doppler and 2-dimensional echocardiography, dipyridamole-induced myocardial ischemia may be detected in a high percentage of CAD patients, providing a sensitive tool for identifying patients with high-risk coronary artery anatomy.

To investigate a physiologic role of coronary prostacyclin (PGI2) and prostaglandin E2 (PGE2) 30 patients who were not affected by coronary heart disease were evaluated for coronary hemodynamics and coronary PGI2 and PGE2 production. Inhibition of coronary prostaglandin biosynthesis by ketoprofen (1 mg/kg) or aspirin (15 mg/kg) administered intravenously did not significantly change coronary hemodynamics in resting conditions. In all patients cold pressor tests induced significant increases in coronary blood flow (p less than 0.001) and decreases in coronary vascular resistance (p less than 0.001) without changes in cardiac oxygen extraction and with consequent increases in calculated myocardial oxygen consumption. Simultaneously, a marked increase in coronary PGI2 (as 6-keto-PGF1 alpha) and PGE2 formation was observed (p less than 0.001). Both ketoprofen (1 mg/kg) and aspirin (15 mg/kg) administration completely abolished PGI2 and PGE2 formation that was induced by cold pressor test and caused a paradoxical increase in coronary vascular resistance (ketoprofen: p less than 0.02; aspirin: p less than 0.05). The results of this study support a physiologic role for the coronary prostaglandins in modulating coronary vascular response to sympathetic stimulation in nonischemic patients.