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In 40 patients with chronic moderate to severe aortic regurgitation, brain natriuretic peptide, N-brain natriuretic peptide, and atrial natriuretic peptide were higher in symptomatic patients compared with asymptomatic patients after adjustment for age, gender, and ejection fraction, but each natriuretic peptide correlated weakly with echocardiographic measures of left ventricular size and function. In patients with chronic aortic regurgitation, measurement of natriuretic peptide levels may provide information on left ventricular function in addition to echocardiography. [ABSTRACT FROM AUTHOR]

Objective: The Multi-Ethnic New Zealand Study of Acute Coronary Syndromes (MENZACS) was established to investigate the drivers of secondary events after first-time acute coronary syndrome (ACS), including addressing inequitable outcomes by ethnicity. Herein, the first clinical outcomes and prognostic modelling approach are reported., Methods: First, in 28 176 New Zealanders with first-time ACS from a national registry, a clinical summary score for predicting 1-year death/cardiovascular readmission was created using Cox regression of 20 clinical variables. This score was then calculated in the 2015 participant MENZACS study to represent clinical risk. In MENZACS, Cox regression was used to assess N-terminal pro-B-type natriuretic peptide (NT-proBNP) as a prognostic marker for death/cardiovascular readmission in four models, adjusting for (1) age and sex; (2) age, sex, ethnicity; (3) clinical summary score; (4) clinical summary score and ethnicity., Results: Of the 2015 MENZACS participants (mean age 61 years, 79% male, 73% European, 14% Māori, 5% Pacific people), 2003 were alive at discharge. Of the 2003, 416 (20.8%) experienced all-cause death/cardiovascular readmission over a median of 3.5 years. In a simple model, age, male sex, Māori ethnicity and NT-proBNP levels were significant predictors of outcome. After adjustment for the clinical summary score, which includes age and sex, NT-proBNP and ethnicity were no longer statistically significant: log 2 (NT-proBNP) hazard ratio (HR) 1.03, 95% confidence interval (95% CI) 0.98 to 1.08, p=0.305; Māori ethnicity HR 1.26, 95% CI 0.97 to 1.62, p=0.084., Conclusions: In 2015 patients with first-time ACS, recurrent events were common (20.8%). Increasing NT-proBNP levels and Māori ethnicity were predictors of death/cardiovascular readmission, but not after adjustment for the 20 clinical risk factors represented by the clinical summary score., Trial Registration Number: ACTRN12615000676516., Competing Interests: Competing interests: JH is a full-time employee of Novo Nordisk Research Centre Oxford Ltd. KKP and AMR are on the Editorial Board for BMJ Heart., (© Author(s) (or their employer(s)) 2023. No commercial re-use. See rights and permissions. Published by BMJ.)

Cardiovascular imaging studies provide a multitude of structural and functional data to better understand disease mechanisms. While pooling data across studies enables more powerful and broader applications, performing quantitative comparisons across datasets with varying acquisition or analysis methods is problematic due to inherent measurement biases specific to each protocol. We show how dynamic time warping and partial least squares regression can be applied to effectively map between left ventricular geometries derived from different imaging modalities and analysis protocols to account for such differences. To demonstrate this method, paired real-time 3D echocardiography (3DE) and cardiac magnetic resonance (CMR) sequences from 138 subjects were used to construct a mapping function between the two modalities to correct for biases in left ventricular clinical cardiac indices, as well as regional shape. Leave-one-out cross-validation revealed a significant reduction in mean bias, narrower limits of agreement, and higher intraclass correlation coefficients for all functional indices between CMR and 3DE geometries after spatiotemporal mapping. Meanwhile, average root mean squared errors between surface coordinates of 3DE and CMR geometries across the cardiac cycle decreased from 7 ± 1 to 4 ± 1 mm for the total study population. Our generalised method for mapping between time-varying cardiac geometries obtained using different acquisition and analysis protocols enables the pooling of data between modalities and the potential for smaller studies to leverage large population databases for quantitative comparisons., (© 2023. The Author(s).)

Segmentation of the left ventricle (LV) in echocardiography is an important task for the quantification of volume and mass in heart disease. Continuing advances in echocardiography have extended imaging capabilities into the 3D domain, subsequently overcoming the geometric assumptions associated with conventional 2D acquisitions. Nevertheless, the analysis of 3D echocardiography (3DE) poses several challenges associated with limited spatial resolution, poor contrast-to-noise ratio, complex noise characteristics, and image anisotropy. To develop automated methods for 3DE analysis, a sufficiently large, labeled dataset is typically required. However, ground truth segmentations have historically been difficult to obtain due to the high inter-observer variability associated with manual analysis. We address this lack of expert consensus by registering labels derived from higher-resolution subject-specific cardiac magnetic resonance (CMR) images, producing 536 annotated 3DE images from 143 human subjects (10 of which were excluded). This heterogeneous population consists of healthy controls and patients with cardiac disease, across a range of demographics. To demonstrate the utility of such a dataset, a state-of-the-art, self-configuring deep learning network for semantic segmentation was employed for automated 3DE analysis. Using the proposed dataset for training, the network produced measurement biases of -9 ± 16 ml, -1 ± 10 ml, -2 ± 5 %, and 5 ± 23 g, for end-diastolic volume, end-systolic volume, ejection fraction, and mass, respectively, outperforming an expert human observer in terms of accuracy as well as scan-rescan reproducibility. As part of the Cardiac Atlas Project, we present here a large, publicly available 3DE dataset with ground truth labels that leverage the higher resolution and contrast of CMR, to provide a new benchmark for automated 3DE analysis. Such an approach not only reduces the effect of observer-specific bias present in manual 3DE annotations, but also enables the development of analysis techniques which exhibit better agreement with CMR compared to conventional methods. This represents an important step for enabling more efficient and accurate diagnostic and prognostic information to be obtained from echocardiography., Competing Interests: MN was the CSO of HeartLab (NZ) Ltd. JD’h holds research contracts with GE Vingmed. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2023 Zhao, Ferdian, Maso Talou, Quill, Gilbert, Wang, Babarenda Gamage, Pedrosa, D’hooge, Sutton, Lowe, Legget, Ruygrok, Doughty, Camara, Young and Nash.)

Diagnosis and prognostication in acute coronary syndromes (ACS) is achieved using a combination of clinical factors and biomarkers, notably cardiac troponin and B type natriuretic peptide and its N terminal fragment NT-proBNP. However, there are numerous biomarkers that have been shown to be associated with ACS, with variable incremental utility. This brief review focusses on some promising emerging biomarkers in ACS, discussed according to pathophysiologic mechanism, as well as diagnostic and prognostic utility., (Copyright © 2022 Australian and New Zealand Society of Cardiac and Thoracic Surgeons (ANZSCTS) and the Cardiac Society of Australia and New Zealand (CSANZ). Published by Elsevier B.V. All rights reserved.)

Aims: Left ventricular (LV) volumes estimated using three-dimensional echocardiography (3D-echo) have been reported to be smaller than those measured using cardiac magnetic resonance (CMR) imaging, but the underlying causes are not well-understood. We investigated differences in regional LV anatomy derived from these modalities and related subsequent findings to image characteristics. Methods and Results: Seventy participants (18 patients and 52 healthy participants) were imaged with 3D-echo and CMR (<1 h apart). Three-dimensional left ventricular models were constructed at end-diastole (ED) and end-systole (ES) from both modalities using previously validated software, enabling the fusion of CMR with 3D-echo by rigid registration. Regional differences were evaluated as mean surface distances for each of the 17 American Heart Association segments, and by comparing contours superimposed on images from each modality. In comparison to CMR-derived models, 3D-echo models underestimated LV end-diastolic volume (EDV) by -16 ± 22, -1 ± 25, and -18 ± 24 ml across three independent analysis methods. Average surface distance errors were largest in the basal-anterolateral segment (11-15 mm) and smallest in the mid-inferoseptal segment (6 mm). Larger errors were associated with signal dropout in anterior regions and the appearance of trabeculae at the lateral wall. Conclusions: Fusion of CMR and 3D-echo provides insight into the causes of volume underestimation by 3D-echo. Systematic signal dropout and differences in appearances of trabeculae lead to discrepancies in the delineation of LV geometry at anterior and lateral regions. A better understanding of error sources across modalities may improve correlation of clinical indices between 3D-echo and CMR., Competing Interests: At study commencement, HH held a position as Advanced Development Product Manager at Siemens Healthineers and provided training toward the acquisition and analysis of 3D-echo data. JD'h currently holds research contracts with GE Vingmed. MN and AY held a research contract with Siemens Healthineers. MN was on the scientific advisory board for HeartLab NZ Ltd. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Zhao, Quill, Gilbert, Wang, Houle, Legget, Ruygrok, Doughty, Pedrosa, D'hooge, Young and Nash.)

Background: Acute coronary syndrome (ACS) events and the ongoing burden of disease can have a significant impact on the subsequent life-course of working age people., Methods: We report 12-month clinical outcomes for 10,822 patients hospitalized with first-time ACS between 2015-2016 and enrolled in the All New Zealand Acute Coronary Syndrome Quality Improvement (ANZACS-QI) registry, with a focus on people of working age (defined as <65 years)., Results: Nearly half (48%) of first-time ACS occurred in people of working age. Compared to those >65 years, these patients had a high burden of cardiovascular risk factors, and were more likely to be male (75% vs 60%), to be of non-European ethnicity (36% vs 15%), and to be living in areas of high deprivation. Subsequent clinical events were common in the younger patients, with 15% dying or being readmitted for cardiovascular causes within 12 months despite high rates of angiography (96%), revascularization (74%) and evidence-based medical therapy at the time of the index ACS event., Conclusions: The high risk factor burden and subsequent high rate of clinical events in working age patients reinforces the need for a longer-term focus on strategies to improve clinical outcomes following first-time ACS., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Background: Competent cardiac auscultation is a declining skill. Digital stethoscopes and hand-held echocardiography (HHE) are modern devices which may improve the accuracy of heart murmur recognition and diagnosis. Their incremental value compared to conventional examination has not been evaluated in depth., Objectives: Our aim was to quantify the utility of digital stethoscopes and HHE as teaching aids to improve medical students' diagnostic accuracy in the evaluation of heart murmurs using a novel clinically weighted scoring system., Design: This pilot study involved eight medical students and eight patients with heart murmurs. Four patients were examined at 2 sessions, 1 week apart. Medical students were randomised into two groups: the 'intervention group' examined patients with a standard and digital stethoscope, and then received demonstration of the valvular lesion with HHE to illustrate the diagnosis. The 'control group' used a standard stethoscope only and were taught using traditional methods. Students' scores were compared to a 'gold standard' derived from a consensus of auscultation findings of three cardiologists., Results: Overall the mean percent correct of total possible score was 65.4% (SD8.4). Using a mixed models ANOVA approach to repeated measures, the mean [95% CI] increase from training to validation period for the control group was 2.5% [-11.5, 16.5] P (Tukey)  = 0.95 and 15.8% [1.7,29.8] P (Tukey)  = 0.027 for the intervention group. Between the validation and training sessions for both groups, there was an increase of 9.1% [1.82, 16.4] in scores (p = 0.018). The mean [95% CI] difference in scores of the control and intervention groups was 1.9% [-5.4, 9.2] (p = 0.59). The Cohen's effect size estimate was 0.9., Conclusion: Digital stethoscopes and hand-held echo may be useful devices for teaching cardiac auscultation. This pilot study provides a novel study design, a heart murmur grading system, and data that will help develop definitive studies to assess new teaching techniques for cardiac auscultation using digital technology.

Background: Cardiovascular (CV) risk factor profiles of people experiencing acute coronary syndromes (ACS) vary with age, and in New Zealand (NZ), Māori and people of Pacific Island descent typically present with ACS at a younger age. We aimed to explore age- and ethnicity-related differences in CV risk factors in a large NZ cohort with first-time ACS., Methods: The All NZ Acute Coronary Syndrome Quality Improvement program (ANZACS-QI) registry collects comprehensive data for patients admitted with ACS at NZ hospitals. This analysis includes patients with no prior atherosclerotic CV disease enrolled from 1 July, 2012 to 30 June, 2015., Results: 14,190 patients had confirmed ACS, 8493 (60%) patients with no prior CVD comprised the study cohort. The mean age was 64 years, 25% were aged <55years, and 66% were male. Those aged <55years were more likely than older patients to be current smokers (48% vs 19%), have higher body mass index (BMI) (48% vs 34% with BMI≥30kg/m 2 ), and higher total cholesterol:HDL ratios (≥4.0, 70% vs 50%), all p<0.001. Sixteen per cent of those <55years had diabetes; these patients often had a BMI≥30kg/m 2 (67%) and higher median HbA1c than older patients with diabetes (69mmol/mol vs 55mmol/mol). Māori and people of Pacific Island descent were overrepresented in the younger age group; these patients had a very high risk factor burden., Conclusions: A quarter of NZ patients admitted to hospital with a first-time CV disease event are aged <55years. Younger patients have a very high risk factor burden: half are current smokers, half have a BMI≥30kg/m 2 , and 16% have diabetes., (Copyright © 2017 Australian and New Zealand Society of Cardiac and Thoracic Surgeons (ANZSCTS) and the Cardiac Society of Australia and New Zealand (CSANZ). Published by Elsevier B.V. All rights reserved.)

Aims: New Zealand (NZ) patients are recommended to undergo an 'adjusted' Framingham score to assess their cardiovascular (CVS) risk. The current (2009) NZ CVS Risk Guideline does not recommend the use of a 'calcium score' as an additional risk tool, although it has been shown to be powerfully predictive of CVS events above the predictive power of traditional Framingham risk factors. Calcium scores of >400 are very strongly predictive of a future CVS event and give direct evidence of atheromatous disease in the coronary circulation. Identification of people with advanced, premature coronary atheroma would allow early treatment of those who may benefit from more vigorous preventative strategies, including statin therapy., Methods: Using a prospectively acquired, comprehensive database we audited the first 1000 patients (7 August 2006 to 28 November 2008) to undergo a 64-slice computed tomographic (CT) cardiac angiogram (GE Light Speed), which included a scan for a 'calcium score', at the Mercy Hospital, Auckland. We excluded 58 patients who had experienced one or more of a previous myocardial infarction (MI) (n=21), coronary artery bypass graft (CABG) surgery (n=15), percutaneous coronary intervention (PCI) (n=13) or stroke (n=21) and who therefore already had definite evidence of vascular disease and would be automatically placed in a high risk strata. We calculated each patient's Framingham risk from the original 'Anderson' equation, used by the 1996 NZ CVS risk Guideline, and the 'adjusted' Framingham 5-year CVS risk using the NZ Guidelines Group 2003/2009 recommendations, and then compared this with the observed calcium scores., Results: The mean patient age was 56 (SD 9) years; 364 (39%) patients were female, 82% patients were Caucasian. 41% were current (4.6%) or previous (36%) cigarette smokers, 35% had a history of hypertension, 44% hyperlipidaemia and 5.6% had diabetes mellitus. The percentage of patients at 'low' 5-Year CVS risk (0-10% 5-year risk), using the 1996 and 2003/2009 guideline methods, was 78% and 58% respectively. Of patients in these Framingham 'low-risk' groups, 10% and 8.8% had a calcium score of >400 Agatston units, indicating that they were actually at very high CVS risk, and 203 (28%) and 147 (27%) respectively had a calcium score of >100 Agatston units, indicating that they were actually at 'high risk' and not 'low risk'., Conclusion: Approximately 10% to 27% of patients with a low CVS risk as assessed by the established Framingham equation have a markedly increased calcium score and hence a significantly increased risk of a CVS event. Currently promoted methods of risk assessment may be inadvertently, falsely re-assuring these patients. Clinicians managing patients may consider a calcium score as an additional tool to the standard risk assessment strategies.

Background: Some patients continue to have significant heart failure symptoms despite optimal medical therapy., Methods: We describe a first-in-human experience with an implantable non-blood-contacting extra-ascending aortic counterpulsation heart assist system (C-Pulse) in 5 end-stage heart failure patients, aged 54 to 73 years., Results: All patients improved by 1 NYHA class and improvements in invasive hemodynamics were documented in 3 patients. Three of 5 patients (60%) had infectious complications. Two patients were explanted at 5 and 7 weeks, respectively, as a result of mediastinal infection related to the implant procedure. One patient was successfully transplanted at 1 month and 1 remained hemodynamically improved on the device at 6 months but suffered infective complications. The device and protocol have been modified as a result of this pilot study with a further multicenter safety study underway., Conclusions: Although feasibility of this device is suggested by this pilot study, safety and efficacy will need to be examined in a larger cohort with longer follow-up., (Copyright © 2010 International Society for Heart and Lung Transplantation. Published by Elsevier Inc. All rights reserved.)

Aims: Left ventricular (LV) hypertrophy and abnormal non-invasive measures of LV diastolic function are common in patients with severe aortic stenosis (AS) but their prognostic importance is uncertain. This study aimed to determine whether tissue Doppler measures of LV systolic and/or diastolic function or echocardiographic LV hypertrophy are useful for risk stratifying asymptomatic patients with severe calcific AS., Methods and Results: One hundred and eighty-three initially asymptomatic patients with moderate or severe AS (valve area mean 0.96 ± SD 0.3 cm(2)) and a normal LV ejection fraction were followed for median 31 (IQR 14-40) months. Peak systolic (S') and diastolic (E') mitral annular velocities and LV mass were measured by echocardiography at baseline and during follow-up. During follow-up 106 (58%) patients suffered symptomatic deterioration, including three sudden deaths and one resuscitated cardiac arrest. Peak aortic velocity (for 0.5 m/s increase HR = 1.43, 95% CI 1.25, 1.64, P < 0.0001) and aortic valve area (-0.1 cm(2)/m(2) HR = 1.23, 95% CI 1.12, 1.35, P = 0.004) at baseline were most strongly associated with symptomatic deterioration. After peak aortic velocity adjustment neither LV mass index nor any measure of LV systolic or diastolic function was associated with symptomatic deterioration (P > 0.2 for all)., Conclusion: In patients with calcific AS who have a normal LV ejection fraction the severity of stenosis is the most important correlate of symptomatic deterioration. Tissue Doppler measures of LV systolic and diastolic function and LV mass provide limited predictive information after accounting for the severity of stenosis.

Aims: Both raised plasma levels of B-type natriuretic peptide (BNP) and an abnormal exercise response predict adverse clinical outcomes in aortic stenosis (AS). This study examines the relationship between the response to treadmill exercise and plasma levels of BNP in AS., Methods and Results: 34 asymptomatic patients with moderate or severe AS (mean valve area 0.96+/-0.3 cm(2)) and 15 age matched controls underwent echocardiography, treadmill exercise testing, and BNP analysis. Compared to control subjects, AS patients had a higher left ventricular mass index, (133+/-50 vs 106+/-24 g/m(2), p=0.03), higher E/E' ratio, (10.6+/-3.6 vs 6.7+/-1.8, p=<0.0001), higher ejection fraction, (65+/-6 vs 59+/-6%, p=0.03), elevated resting BNP (11.4+/-6.5 vs 7.4+/-4.0 pmol/L, p=0.03) and shorter exercise duration (8.2+/-3.0 min vs 10.9+/-2.6 min, p=0.002). AS patients with an increase in systolic BP of 20 mmHg (13.8+/-6.1 vs 8.6+/-6.0 pmol/L, p=0.003). The BNP measured at peak exercise was also associated with the BP response (p=0.003). The area under the receiver operator curve to predict an abnormal BP response to exercise was 0.82 for BNP measured at rest but only 0.46 for aortic valve area. There was a modest association between raised BNP and lower exercise capacity., Conclusion: In patients with AS there is an association between BNP and an abnormal BP response to exercise. Further study is needed to determine the incremental prognostic value of BNP and exercise testing in asymptomatic AS.

Objective: To determine whether longitudinal left ventricular systolic function measured by Doppler tissue imaging (DTI) after exercise can identify early left ventricular dysfunction in asymptomatic patients with moderate-severe aortic stenosis., Design: Case-control study., Setting: Outpatient cardiology departments., Patients: 20 patients with aortic stenosis, with or without equivocal symptoms, a peak aortic valve velocity > or =3 m/s, and left ventricular ejection fraction >50% and 15 aged-matched normal controls., Interventions: Echocardiogram performed at rest and immediately after treadmill exercise., Main Outcome Measures: The peak systolic velocity of the lateral mitral annulus (S') by DTI at rest and immediately after exercise, exercise capacity, exercise systolic blood pressure and the plasma level of B-type natriuretic peptide (BNP)., Results: For patients with aortic stenosis, mean (SD) aortic valve area was 0.95 (0.3) cm(2). At rest, S' was similar for patients with aortic stenosis and controls, respectively (8.5 (1.5) vs 9.1 (1.8) cm/s, p = 0.15). However, after exercise, S' (12.2 (3.2) vs 17 (2.8) cm/s, p<0.001) and the increase in S' between rest and exercise (4 (3) vs 7.9 (1.5) cm/s, p<0.001) were lower in patients with aortic stenosis. In patients with aortic stenosis, a smaller increase in S' after exercise was associated with lower exercise capacity (r = 0.5, p = 0.02), a smaller increase in exercise systolic blood pressure (r = 0.6, p = 0.005) and higher plasma level of BNP (r = 0.66, p = 0.002)., Conclusion: In asymptomatic patients with moderate-severe aortic stenosis a lower than normal increase in peak systolic mitral annular velocity after treadmill exercise is a marker of early left ventricular systolic dysfunction.

One of the main limitations in using inverse methods for non-invasively imaging cardiac electrical activity in a clinical setting is the difficulty in readily obtaining high-quality data sets to reconstruct accurately a patient-specific geometric model of the heart and torso. This issue was addressed by investigation into the feasibility of using a pseudo-3D ultrasound system and a hand-held laser scanner to reconstruct such a model. This information was collected in under 20 min prior to a catheter ablation or pacemaker study in the electrophysiology laboratory. Using the models created from these data, different activation field maps were computed using several different inverse methods. These were independently validated by comparison of the earliest site of activation with the physical location of the pacing electrodes, as determined from orthogonal fluoroscopy images. With an estimated average geometric error of approximately 8 mm, it was also possible to reconstruct the site of initial activation to within 17.3 mm and obtain a quantitatively realistic activation sequence. The study demonstrates that it is possible rapidly to construct a geometric model that can then be used non-invasively to reconstruct an activation field map of the heart.

In 29 initially asymptomatic patients with aortic stenosis followed for an average of 18 months, patients with a N-terminal pro-brain natriuretic peptide (NT-pro-BNP) level above the normal range at baseline were more likely to develop symptoms during follow-up compared with patients with NT-pro-BNP within normal limits. The average increase in NT-pro-BNP per year was greater for patients who developed symptoms compared with patients who remained asymptomatic. Aortic valve area, peak aortic velocity, and the ejection fraction were less reliable predictors of symptom onset. Measurement of NT-pro-BNP in addition to clinical assessment and echocardiography may allow more reliable follow-up and timing of valve replacement for aortic stenosis.

Three-dimensional transesophageal echocardiography offers promise for improved understanding of mitral leaflet pathology, but it has not been validated quantitatively, nor has the minimum number of imaging planes for satisfactory reconstruction been determined with a rotational scanning geometry. This study assessed its accuracy in vitro by comparing, on a 1 x 1-mm grid, the surfaces of mitral leaflets derived from 5-degree rotational ultrasonic scans with those derived from laser scans of casts of the atrial side of the leaflets. Overall, the ultrasonically derived surface had a mean absolute deviation of 0.65 +/- 0.12 mm from the laser-derived surface. Using only alternate imaging planes (10-degree increments) made no significant difference in the overall distribution of deviations (P =.56), although the distributions on some individual specimens differed markedly. We conclude that 5-degree rotational scanning in vitro can reconstruct the mitral valve leaflets with sufficient accuracy and detail to render clinically important features.

Plasma levels of C-reactive protein were higher in 20 patients with bicuspid or trileaflet degenerative aortic stenosis than in 31 normal controls and in 19 patients with pure aortic regurgitation. C-reactive protein decreased from before to 6 months after aortic valve replacement for aortic stenosis. These observations suggest that aortic stenosis is an inflammatory disease.

Aims: We report our initial experience with the Freestyle aortic bioprosthesis., Methods: This prosthesis was implanted in 40 patients between February 1993 and December 1998. Operative indications were aortic stenosis in 32 patients (80%), aortic regurgitation in seven patients (18%) and a combined lesion in one (3%). The mean patient age was 71.4+/-9.7 (SD) years, with 29 (72%) females. Pre-operative New York Heart Association (NYHA) class was III or IV in 28 (70%). Left ventricular systolic function was impaired in four (10%). Six (15%) patients had undergone previous cardiac surgery. Concomitant procedures were carried out in 21 patients (53%)., Results: Early mortality was zero. Early morbidity included three re-operations for bleeding, one cerebrovascular event, one haemorrhagic complication and one case of valve dysfunction. At follow up (range 4.6 to 75.6 months, mean 29.5+/-25.5) there has been one (3%) late death which was non valve related, one (3%) episode of study-valve endocarditis, and three (8%) thromboembolic episodes. NYHA Class was I or II in all but one survivor. Echocardiographic follow-up has shown no further instances of valve dysfunction with satisfactory haemodynamic parameters at 24-months post-operation, and a significant and sustained regression of left ventricular mass., Conclusions: The initial experience with the Freestyle valve is that it results in good clinical and haemodynamic performance, suggesting it as an ideal bioprosthesis for this patient group.

We report the case of a ventricular septal aneurysm in a patient with a previous inferior myocardial infarction. Two-dimensional echocardiography demonstrated a cystic cavity in the muscular septum with a small communication into the left ventricle. No evidence of left-to-right shunt was detected with Doppler echocardiography or during left ventriculography.

Background: The Mosaic bioprosthesis is a new generation stented porcine valve., Methods: Between May 1995 and April 1998, this valve was implanted in the aortic position in 98 patients (70 men; mean age, 69.2 years [34.2 to 83.6 years]). Preoperatively 35 patients were in New York Heart Association functional class 3 or 4. Fifty-nine patients underwent concomitant procedures. The mean duration at follow-up in January 1999 was 23.7 +/- 10.2 months (0.3 to 39.4 months) and totaled 193 patient-years. All but one survivor was in New York Heart Association class 1 or 2., Results: Early complications included 1 death, 3 reoperations for bleeding, greater than mild regurgitation (paravalvar) in 1 patient and thromboembolism in 4 patients. Late complications included four deaths, study-valve endocarditis in 3 patients, more than mild regurgitation or hemolysis in 2, and thromboembolism in 2 patients. Late follow-up echocardiography in all survivors showed a mean transaortic gradient of 13.6 +/- 6.7 mm Hg, and an aortic valve area of 1.80 +/- 0.61 cm2. Valve replacement was followed by a significant and sustained decrease in left ventricular mass for all valve sizes. There has been no primary structural valve failure., Conclusions: The early experience with the Mosaic valve in the aortic position has been promising.

Objectives: To compare mitral annular shape and motion throughout the cardiac cycle in patients with normal hearts versus those with functional mitral regurgitation (FMR)., Background: The causes of mitral regurgitation without valvular disease are unclear, but the condition is associated with changes in annular shape and dynamics. Three-dimensional (3D) imaging provides a more comprehensive view of annular structure and allows accurate reconstructions at high spatial and temporal resolution., Methods: Nine normal subjects and 8 patients with FMR undergoing surgery underwent rotationally scanned transesophageal echocardiography. At every video frame of 1 sinus beat, the mitral annulus was manually traced and reconstructed in 3D by Fourier series. Annular projected area, nonplanarity, eccentricity, perimeter length, and interpeak and intervalley spans were determined at 10 time points in systole and 10 points in diastole., Results: The mitral annulus in patients with FMR had a larger area, perimeter, and interpeak span than in normal subjects (P <.001 for all). At mid-systole in normal annuli, area and perimeter reach a minimum, nonplanarity is greatest, and projected shape is least circular. These cyclic variations were not significant in patients with FMR. Annular area change closely paralleled perimeter change in all patients (mean r = 0.96 +/- 0.07)., Conclusions: FMR is associated with annular dilation and reduced cyclic variation in annular shape and area. Normal mitral valve function may depend on normal annular 3D shape and dimensions as well as annular plasticity. These observations may have implications for design and selection of mitral annular prostheses.

Background: An increasing number of patients aged 80 years and over are being considered and accepted for cardiac surgery., Aim: To review the experience of surgery in this elderly group of patients at our institution., Methods: Hospital records of octogenarians undergoing surgery between January 1995 and September 1998 were reviewed and follow-up was obtained by general practitioner (GP) and patient questionnaires., Results: Thirty-seven patients underwent cardiac surgery. The mean age was 82.8+/-1.4 years (range 80.8 to 86.2 years). Twenty-three (62%) were male. All were independent pre-operatively with severe symptoms and minor co-existing morbidity. All operations were urgent except two (emergency). Twenty patients (54%) had isolated coronary surgery, six (16%) aortic valve replacement alone, and 11 (30%) combined surgery. There were four (11%) early deaths and five (14%) peri-operative neurological events. The mean duration of post-operative intensive care stay was 2.4+/-3.9 days (range 0.05 to 16, median 1.0) and post-operative hospital stay 14.0+/-13.9 days (range 0 to 79, median 11). At the time of follow-up (mean duration 20.0+/-11.2 months) two further patients had died (non-cardiac). Twenty-six of the 31 survivors were living at home (23 independently), one with relatives, and four in residential care. Their cardiac symptoms were well controlled. The GPs of all hospital survivors, and all surviving patients themselves, felt that cardiac surgery had been beneficial., Conclusions: Cardiac surgery in the very elderly has been reserved for those with severe disease or symptoms and little co-morbidity. Early mortality is higher than for the general population undergoing cardiac surgery, but post-operative resource use is acceptable and the intermediate-term outcome for survivors is good.

Left ventricular function and myocardial contractility in aortic stenosis have been intensely studied over the past 40 years. The underlying impetus for a good deal of this work has been to define the interaction between the ventricle and the valve, to predict in an individual patient the clinical course and outcome after aortic valve replacement. Furthermore, the relationship between afterload (wall stress) and contractility has been closely examined. Although wall stress has been shown to be inversely correlated to ejection fraction or fiber shortening, there is wide individual variability for a similar degree of valvular stenosis, which renders interpretation of data regarding left ventricular function and myocardial contractility difficult. A number of other factors affect the response of the left ventricle to chronic pressure overload. The use of stress-shortening relationships in patients with aortic stenosis requires further study before these measures can be advocated for clinical use. This review examines the usefulness of left ventricular wall stress and parameters of left ventricular function in aortic stenosis, dealing with basic concepts, echocardiographic approach, and clinical usefulness.

Background and Methods: The goal of this study was to examine the ability of physical examination to predict valvular aortic stenosis severity and clinical outcome in 123 initially asymptomatic subjects (mean age 63 +/- 16 years, 70% men) followed up for a mean of 2.5 +/- 1.4 years., Results: Doppler aortic jet velocity correlated with systolic murmur intensity (P =.003) and timing (P =.0002), a single second heart sound (P =.01), and carotid upstroke delay (P <.0001) and amplitude (P <.0001). However, no physical examination findings had both a high sensitivity and a high specificity for the diagnosis of severe valvular obstruction. Clinical end points were reached in 56 subjects (46%), including 8 deaths and 48 valve replacements for symptom onset. Univariate predictors of outcome included carotid upstroke delay (P =.0008) and amplitude (P =.0006), systolic murmur grade (P <.0001) and peak (P =.0003), and a single second heart sound (P =.003). On multivariate Cox regression analysis, the only physical examination predictor of outcome was carotid upstroke amplitude (P =.0001)., Conclusions: Although physical examination findings correlate with stenosis severity, echocardiography still is needed to exclude severe obstruction reliably when this diagnosis is suspected.

Accurate measurement of left-ventricular (LV) volume and function are important to monitor disease progression and assess prognosis in patients with heart disease. Existing methods of three-dimensional (3-D) imaging of the heart using ultrasound have shown the potential of this modality, but each suffers from inherent restrictions which limit its applicability to the full range of clinical situations. We have developed a technique for image acquisition using a magnetic-field system to track the 3-D echocardiographic imaging planes and 3-D image analysis software including the piecewise smooth subdivision method for surface reconstruction. The technique offers several advantages over existing methods of 3-D echocardiography. The results of validation using in vitro LV's show that the technique allows accurate measurement of LV volume and anatomically accurate 3-D reconstruction of LV shape and is, therefore, suitable for analysis of regional as well as global function.

Ten phantoms were scanned with a multiplane transesophageal echocardiographic probe in a water bath to assess a new method for three-dimensional modeling of the mitral annulus. The annulus was reconstructed from manually outlined borders with Fourier series in each of the three spatial coordinates. Comparisons with direct measurements by least-squares linear regression gave coefficients of determination of 0.99 for annular height, area, and circumference. Expressed as a percentage of their true values, the mean +/- SD of the errors were -0.1% +/- 3.0% for annular height, -2.8% +/- 3.1% for area, and -0.2% +/- 1.7% for circumference. The mean residual error length for phantoms was 0.64 mm compared with 1.21 mm in nine patients studied during general anesthesia. This method gives accurate and precise measurements of the mitral annulus in vitro and should be valuable for studying its morphology and dynamics in vivo.

Background: Only limited data on the rate of hemodynamic progression and predictors of outcome in asymptomatic patients with valvular aortic stenosis (AS) are available., Methods and Results: In 123 adults (mean age, 63 +/- 16 years) with asymptomatic AS, annual clinical, echocardiographic, and exercise data were obtained prospectively (mean follow-up of 2.5 +/- 1.4 years). Aortic jet velocity increased by 0.32 +/- 0.34 m/s per year and mean gradient by 7 +/- 7 mm Hg per year; valve area decreased by 0.12 +/- 0.19 cm2 per year. Kaplan-Meier event-free survival, with end points defined as death (n = 8) or aortic valve surgery (n = 48), was 93 +/- 5% at 1 year, 62 +/- 8% at 3 years, and 26 +/- 10% at 5 years. Univariate predictors of outcome included baseline jet velocity, mean gradient, valve area, and the rate of increase in jet velocity (all P < or = .001) but not age, sex, or cause of AS. Those with an end point had a smaller exercise increase in valve area, blood pressure, and cardiac output and a greater exercise decrease in stroke volume. Multivariate predictors of outcome were jet velocity at baseline (P < .0001), the rate of change in jet velocity (P < .0001), and functional status score (P = .002). The likelihood of remaining alive without valve replacement at 2 years was only 21 +/- 18% for a jet velocity at entry > 4.0 m/s, compared with 66 +/- 13% for a velocity of 3.0 to 4.0 m/s and 84 +/- 16% for a jet velocity < 3.0 m/s (P < .0001)., Conclusions: In adults with asymptomatic AS, the rate of hemodynamic progression and clinical outcome are predicted by jet velocity, the rate of change in jet velocity, and functional status.

Objective: To evaluate the effect of aortic valve replacement on left ventricular function, functional status and exercise duration in an adult population with valvular aortic stenosis., Design: Prospective study of initially asymptomatic patients with pre- and postvalve replacement echocardiography, functional status score and exercise data., Setting: University-affiliated, tertiary care teaching hospital., Patients: Valvular aortic stenosis patients referred from academic and private practice internists and cardiologists (n = 34, 65% men, mean age 68 +/- 11 years, preoperative aortic valve area 0.9 +/- 0.4 cm2)., Interventions: Annual Doppler echocardiography, functional status questionnaires and, if possible, Bruce protocol maximal exercise tolerance tests., Main Results: Aortic valve replacement resulted in a decrease in maximum jet velocity (pre 4.7 +/- 0.7 versus post 2.9 +/- 0.7 m/s, P = 0.0001) and left ventricular mass (pre 167 +/- 37 versus post 134 +/- 32 g, P = 0.0001) and an increase in left ventricular ejection fraction (pre 65 +/- 11 versus post 69 +/- 10%, P = 0.05) at rest. However, there was no change in the ratio of early to atrial diastolic filling velocities (pre 1.2 +/- 0.5 versus post 1.4 +/- 0.8, not significant), exercise tolerance as assessed by estimated functional aerobic impairment (pre 26 +/- 32 versus post 22 +/- 27%, not significant) or functional status score (pre 89 +/- 13 versus post 91 +/- 11, not significant)., Conclusions: When the aortic valve is replaced promptly at symptom onset, despite improvement in resting left ventricular systolic performance, there is no evidence of improvement in exercise capacity or functional status.

Three-dimensional (3D) reconstruction from a single esophageal scanning position requires a stable relationship between the probe and the heart. The purpose of this study was to examine the movement of a transesophageal echocardiographic probe during 3D image acquisition. A new dual-axis multiplane probe was used that includes a miniature (6 x 6 x 9 mm) magnetic sensor in the tip. The sensor identifies the probe's 3D position and 3D orientation in space with respect to the location of a magnetic field generator placed beneath the subject. In vivo 3D scanning was performed in five anesthetized, ventilated dogs, with positional determinations acquired every 66 msec. Probe movement was estimated by computing the deviations of each x, y, and z position and orientation determination, compared with the average values during each 3D scan or cardiac cycle. Ten 3D scans were analyzed, involving 263 cardiac cycles and 2328 determinations. The range and SD of the translational movement of the transducer were 2.3 and 0.8 mm, 1.7 and 0.5 mm, and 2.4 and 0.7 mm in x, y, and z directions, respectively, during 3D scanning. Translational movement was more dominant than was rotational movement. Misregistration of three-dimensional reconstructions may be due to subtle probe movement. The ability to monitor probe movement may be helpful in optimizing 3D data sets.