Dilated cardiomyopathy (DCM) is the most common myocardial disease. It not only leads to systolic dysfunction but also diastolic deficiency. We sought to investigate the effect of idiopathic and ischemic DCM on the intraventricular fluid dynamics and myocardial wall mechanics using a 2D axisymmetrical fluid structure interaction model. In addition, we also studied the individual effect of parameters related to DCM, i.e. peak E-wave velocity, end systolic volume, wall compliance and sphericity index on several important fluid dynamics and myocardial wall mechanics variables during ventricular filling. Intraventricular fluid dynamics and myocardial wall deformation are significantly impaired under DCM conditions, being demonstrated by low vortex intensity, low flow propagation velocity, low intraventricular pressure difference (IVPD) and strain rates, and high-end diastolic pressure and wall stress. Our sensitivity analysis results showed that flow propagation velocity substantially decreases with an increase in wall stiffness, and is relatively independent of preload at low-peak E-wave velocity. Early IVPD is mainly affected by the rate of change of the early filling velocity and end systolic volume which changes the ventriculo:annular ratio. Regional strain rate, on the other hand, is significantly correlated with regional stiffness, and therefore forms a useful indicator for myocardial regional ischemia. The sensitivity analysis results enhance our understanding of the mechanisms leading to clinically observable changes in patients with DCM.
INTRODUCTION: Peripartum cardiomyopathy (PPCM) is an uncommon form of congestive heart failure, affecting obstetric patients around the time of delivery. The epidemiology of PPCM is infrequently reported. This study was undertaken to define the prevalence, presentation and outcome of PPCM among women giving birth in a teaching hospital in Malaysia.
METHODS: A retrospective case record analysis was conducted on all patients admitted and diagnosed with PPCM at the University Malaya Medical Centre, Kuala Lumpur, Malaysia, from 1 January 2000 to 31 December 2009. All deliveries were undertaken in the same hospital.
RESULTS: A total of 12 patients were diagnosed with PPCM during the ten-year study period. The prevalence of PPCM was 2.48 in 100,000 (1 in 40,322) live births. Nine women were diagnosed with PPCM within five months of delivery. Three women had twin pregnancies. There was one death in the group (mortality rate 8.3%). The mean left ventricular ejection fraction at the time of diagnosis was 28.9% ± 8.5% (range 15%-40%). Following the index event, left ventricular function normalised in six of the nine patients (66.7%) who underwent subsequent echocardiography one year later. All patients were treated with standard heart failure therapy. Two patients with normalised left ventricular function had subsequent pregnancies - one pregnancy was terminated at seven weeks and the other patient delivered uneventfully at full term.
CONCLUSION: PPCM is uncommon. The outcome in our series was favourable, with 66.7% of patients with PPCM recovering their left ventricular function. The mortality rate was 8.3%.
A 45-year-old woman with poorly controlled hypertension and diabetes mellitus presented with left iliac fossa pain, constipation alternating with diarrhea, and weight loss. She had been diagnosed with idiopathic cardiomyopathy five years previously. Echocardiogram had shown a left ventricular ejection fraction (LVEF) of 35%; coronary angiogram was normal. Colonoscopy revealed sigmoid colitis with stenosis. Abdominal computed tomography revealed a 5 cm right adrenal tumor. Twenty-four hour urinary free catecholamines and fractionated metanephrine excretion values were elevated, confirming pheochromocytoma. Her colitis resolved after one month of adrenergic blockade. Repeat echocardiogram showed improvement of LVEF to 65%. After laparoscopic right adrenalectomy, the patient's hypertension resolved, and diabetic control improved. Timely management avoided further morbidity and potential mortality in our patient.