Fahed Bitar

Pregnancy-Associated Cardiomyopathy Clinical Characteristics and a Comparison Between Early and Late Presentation

Background—Cardiomyopathy associated with pregnancy was first described more than half a century ago. However, because of its rare occurrence and geographical differences, the clinical profile of this condition has remained incompletely defined. Methods and Results—Data obtained from 123 women with a history of cardiomyopathy diagnosed during pregnancy or the postpartum period were reviewed. One hundred women met traditional criteria of peripartum cardiomyopathy; 23 were diagnosed with pregnancy-associated cardiomyopathy earlier than the last gestational month. Peripartum cardiomyopathy patients had a mean age of 31±6 years and were mostly white (67%). Common associated conditions were gestational hypertension (43%), tocolytic therapy (19%), and twin pregnancy (13%). Left ventricular ejection fraction at the time of diagnosis was 29±11% and improved to 46±14% (P≤0.0001) at follow-up. Normalization of left ventricular ejection fraction occurred in 54% and was more likely in patients with left ventricular ejection fraction >30% at diagnosis. Maternal mortality was 9%. A comparison between the peripartum cardiomyopathy and early pregnancy-associated cardiomyopathy groups revealed no differences in age, race, associated conditions, left ventricular ejection fraction at diagnosis, its rate and time of recovery, and maternal outcome. Conclusions—This study helps to define the clinical profile of patients with pregnancy-associated cardiomyopathy diagnosed in the United States. Clinical presentation and outcome of patients with pregnancy-associated cardiomyopathy diagnosed early in pregnancy are similar to those of patients with traditional peripartum cardiomyopathy. These 2 conditions may represent a continuum of a spectrum of the same disease.

Clinical Profile and Predictors of Complications in Peripartum Cardiomyopathy

BACKGROUND Clinical profile and predictors of major adverse events (MAE) associated with peripartum cardiomyopathy (PPCM) have not been characterized. METHODS AND RESULTS A retrospective review and analysis of clinical data of 182 patients with PPCM. Forty-six patients had >or=1 MAE, including death (13), heart transplantation (11), temporary circulatory support (4), cardiopulmonary arrest (6), fulminant pulmonary edema (17), thromboembolic complications (4), and defibrillator or pacemaker implantation (10). Diagnosis of PPCM was delayed >or=1 week in 48% of patients with MAE that preceded the diagnosis in 50% of these patients. Seven (32%) of the surviving patients who had MAE and did not undergo heart transplantation had residual brain damage. Significant predictors of MAE were: left ventricular ejection fraction <or=25% (HR 4.20, CI 2.04-8.64) and non-Caucasian background(HR 2.16, CI 1.17- 3.97). These predictors in addition to diagnosis delay (HR 5.51, CI 1.21-25.04) were also associated with death or heart transplantation. CONCLUSIONS 1. PPCM may be associated with mortality or severe and lasting morbidity. 2. Incidence of MAE is higher in non-Caucasians and in women with left ventricular ejection fraction <or=25%. 3. Diagnosis of PPCM is often delayed and preceded by MAE. 4. Increased awareness of PPCM is required for early diagnosis and aggressive therapy in an attempt to prevent complications.

Intravenous Nitroglycerin in the Treatment of Decompensated Heart Failure: Potential Benefits and Limitations:

Acute decompensated heart failure (ADHF) is a common cause of hospitalizations. Intravenous nitroglycerin is widely used in the treatment of this condition. The use of this drug is based on its nitric oxide-mediated vasodilatory effect, which can lead to beneficial hemodynamic effects as well as improvement of myocardial ischemia and reduction of mitral regurgitation. However, information regarding the use of nitroglycerin for ADHF is limited to mostly hemodynamic evaluations in small groups of patients without cardiovascular outcome data. A single randomized, placebo controlled study that evaluated commonly used doses of nitroglycerin in patients with ADHF was disappointing and failed to show a significant hemodynamic effect or improvement of symptoms compared with placebo. The potential benefit of nitroglycerin seems to be limited by a decreased vasodilatory response in patients with heart failure, which requires an active titration of the drug and the use of high doses (>120 µg/min). In addition, the initial beneficial hemodynamic effect achieved with the appropriate dose of nitroglycerin is associated with neurohumoral activation and limited by an early development of nitrate tolerance that leads to a marked attenuation of the initial effect. More information obtained in large-scale studies that are appropriately designed to evaluate the effect of variable doses of nitroglycerin on short- and long-term cardiovascular outcome, with and without interventions shown to prevent nitrate tolerance, is needed before intravenous nitroglycerin can be recommended as a standard therapy for ADHF.

Evaluation of the clinical relevance of baseline left ventricular ejection fraction as a predictor of recovery or persistence of severe dysfunction in women in the United States with peripartum cardiomyopathy.

BACKGROUND Baseline left ventricular ejection fraction (LVEF) has been shown to be associated with likelihood of recovery in patients with peripartum cardiomyopathy (PPCM). The clinical relevance of this association for individual patients is unclear. METHODS AND RESULTS We analyzed baseline parameters of LVEF in 187 PPCM patients with ≥6 months follow-up data in an attempt to detect the value of baseline LVEF as a predictor of early recovery or persistence of severe LV dysfunction. Recovery of LV function (LVEF ≥50%) at 6 months after diagnosis was found in 115 patients (61%). Multivariate analysis identified baseline LVEF >30% as a significant predictor for recovery (odds ratio 5.2, 95% confidence interval 1.96-7.70; P > .0001). Recovery of LV function was 6.4-fold higher in women with baseline LVEF ≥ 30% (group III) and 3.9-fold higher in women with LVEF 20%-29% (group II) compared with those with LVEF 10%-19% (group I). Failure to achieve full recovery was seen in 63% of group I patients, 32% of group II (P = .03), and 21% of group III (P = .02 vs group I). Failure to achieve LVEF ≥30% was seen in 30% of group I patients and 13% of group II (P = .09). CONCLUSIONS Early recovery in patients with PPCM is significantly related to the degree of myocardial insult at time of diagnosis. Baseline LVEF however, has a limited sensitivity for prediction of failure to improve in individual patients and can not be used as an indication for premature use of aggressive therapy including devices or cardiac transplantation.

Variable Response of Conductance and Resistance Coronary Arteries to Endothelial Stimulation in Patients With Heart Failure Due to Nonischemic Dilated Cardiomyopathy

Attenuation of endothelial-dependent coronary vasodilation has been reported in idiopathic dilated cardiomyopathy and anatomically normal coronaries; however, data are insufficient for understanding the incidence and extent of this finding. The response of conductance and resistance coronary arteries to endothelial stimulation with acetylcholine was examined in 25 patients. Coronary blood flow had a variable response to acetylcholine and suggested coronary endothelial dysfunction in approximately half of the patients. Abnormal endothelial dysfunction involved the large conductance epicardial coronary arteries and the small resistance vessels. Abnormal endothelial response of coronary blood flow to acetylcholine could not be predicted by demographic and hemodynamic data. Conclusions: Coronary artery endothelial function is heterogeneous in patients with idiopathic dilated cardiomyopathy. Endothelial dysfunction is present in approximately half of the cases and involves both resistance as well as conductance coronary blood vessels. Furthermore, coronary endothelial function cannot be predicted by demographic and hemo-dynamic parameters or left ventricular ejection fraction.