The outcome of patients with peripartum cardiomyopathy and consecutive implantation of a left ventricular assist device

Cardiogenic Shock and Utilization of Mechanical Circulatory Support in Pregnancy

Maternal mortality rates are rising in the United States, a trend which is in contrast to that seen in other high-income nations. Cardiovascular disease and hypertensive disorders of pregnancy are consistently the leading causes of maternal mortality both in the United States and globally, accounting for about one-quarter to one-third of maternal and peripartum deaths. A large proportion of cardiovascular morbidity and mortality stems from acquired disease in the context of cardiovascular risk factors, which include obesity, pre-existing diabetes and hypertension, and inequities in care from maternal care deserts and structural racism. Patients may also become pregnant with preexisting structural heart disease, or acquire disease throughout pregnancy (ex: spontaneous coronary artery dissection, peripartum cardiomyopathy), and be at higher risk of pregnancy-related cardiovascular complications. While risk-stratification tools including the modified World Health Organization (mWHO) classification, Cardiac Disease in Pregnancy (CARPREG II) and Zwangerschap bij Aangeboren HARtAfwijking/Pregnancy in Women with Congenital Heart Disease (ZAHARA) have been designed to help physicians identify patients at increased risk for adverse pregnancy outcomes and who may therefore benefit from referral to a tertiary care center, the limitation of these scores is their predominant focus on patients with known preexisting heart disease. As such, identifying patients at risk for pregnancy complications presents a significant challenge, and it is often patients with high-risk cardiovascular substrates prior to or during pregnancy who are at a highest risk for adverse pregnancy outcomes including cardiogenic shock.

Peripartum Cardiogenic Shock and Mechanical Circulatory Support

Despite remarkable improvements in the past two decades, the annual cardiovascular mortality rate has remained higher for women than for men. Pregnant women represent an underinvestigated population in clinical research, and the mechanisms of long-term cardiovascular complications in women with obstetric complications remain to be elucidated. Regarding advanced heart failure during pregnancy, interventional approaches are effective but still underutilised. Percutaneous mechanical circulatory support is a valuable option for peripartum cardiogenic shock, although its use during pregnancy is still limited. Survival rates have improved in recent years, but further emphasis on the importance of early recognition and initiation of heart failure treatment in this patient group is warranted. The aims of this review are to summarise the current literature on the implementation of mechanical circulatory support in cardiogenic shock during pregnancy and delivery and to understand the role of percutaneous ventricular assist devices in the management of such conditions.

Meta-Analysis of Long-Term (>1 Year) Cardiac Outcomes of Peripartum Cardiomyopathy

Peripartum cardiomyopathy is the development of heart failure toward the end of pregnancy or in the months after delivery in the absence of other attributable causes, with left ventricular systolic dysfunction and a left ventricular ejection fraction (LVEF) generally <45%. Given that patients are relatively young at the time of diagnosis, this study was performed to summarize current evidence surrounding the long-term cardiac outcomes. MEDLINE, Embase, Cochrane CENTRAL, and CINAHL were searched for original studies that reported long-term (>1 year) patient outcomes. Of the 3,144 total records identified, 62 studies involving 4,282 patients met the selection criteria. The mean LVEF was 28% at diagnosis and 47% at the time of the last follow-up. Approximately half of the patients achieved myocardial recovery (47%), most commonly defined as an LVEF >50% (n = 21). The prevalence of implantable cardioverter-defibrillator use, left ventricular assist device implantation, and heart transplantation was 12%, 7%, and 11%, respectively. The overall all-cause mortality was 9%, and despite having more cardiovascular risk factors, patients residing in high-income countries had superior outcomes, including reduced rates of mortality.

Clinical characteristics and long-term outcomes in patients with peripartum cardiomyopathy (PPCM) receiving left ventricular assist devices (LVAD)

BACKGROUND

Peripartum cardiomyopathy (PPCM) is a rare cause of heart failure (HF), presenting with left ventricular (LV) systolic dysfunction either at the end of pregnancy or in the months following delivery. In rare cases, PPCM leads to severe impairment of LV function, refractory cardiogenic shock or advanced HF. LV assist devices (LVAD) have been shown to be a feasible treatment option in advanced HF. However, little is known about long-term outcomes and prognosis of PPCM patients undergoing LVAD implantation.

METHODS

A retrospective analysis of data from PPCM patients undergoing LVAD implantation in two tertiary centers with respect to long-term outcomes was performed.

RESULTS

Twelve patients of median age 30 (18-39) years were included. Eight patients were experiencing cardiogenic shock (INTERMACS 1) at implantation. Seven patients were implanted within 1 month of their PPCM diagnosis. Median duration of LVAD support was 19 (2-92) months with median follow up of 67 (18-136) months (100% complete). In-hospital and 1-year mortality were 0% and 8.3%, respectively. Two patients died on LVAD support, four patients were successfully bridged to transplantation, two patients are still on LVAD, and four were successfully weaned due to sufficient LV recovery (one died after LV function deteriorated again).

CONCLUSION

LVAD treatment of decompensated end-stage PPCM is feasible. Early LVAD provision led to hemodynamic stabilization in our cohort and facilitated safe LV recovery in one third of these young female patients.

Contemporary Management of Cardiogenic Shock During Pregnancy

Cardiogenic shock is the most extreme cardiovascular disease state during pregnancy. Peripartum cardiomyopathy is the most common cause of cardiogenic shock toward the end of pregnancy and in the early postpartum period. Therapy for cardiogenic shock relies on appropriate phenotyping of shock etiology, severity and ventricular predominance, which are critical in the appropriate selection of medical and mechanical therapy. Mechanical circulatory support may be used as a bridge to recovery or as definitive therapy. Intra-aortic balloon pumps, percutaneous left ventricular assist devices and venoarterial extracorporeal circulatory devices have been successfully used in pregnancy and the postpartum period. The most commonly used mechanical therapy in the pregnant patient is extracorporeal membranous oxygenation circulatory support. The use of mechanical circulatory devices in peripartum cardiomyopathy has contributed to improved survival rates in recent years. Further efforts to identify the optimal mechanical circulatory support strategy for peripartum cardiomyopathy and cardiogenic shock in the peripartum period are needed.

A global perspective on the management and outcomes of peripartum cardiomyopathy: a systematic review and meta-analysis

AIMS

Peripartum cardiomyopathy (PPCM) remains a major contributor to maternal morbidity and mortality worldwide. The disease is associated with various complications occurring mainly early during its course. Reported adverse outcomes include decompensated heart failure, thromboembolic complications, arrhythmias and death. We sought to systematically and comprehensively review published literature on the management, and outcome of women with PPCM across different geographical regions and to identify possible predictors of adverse outcomes.

METHODS AND RESULTS

We performed a comprehensive search of relevant literature (2000 to June 2021) across a number of electronic databases. Cohort, case-control and cross-sectional studies, as well as control arms of randomised controlled trials reporting on six- and/or twelve-month outcomes of PPCM were considered eligible (PROSPERO registration: CRD42021255654). Forty-seven studies (4875 patients across 60 countries) met the inclusion criteria. Haemodynamic and echocardiographic parameters were similar across all continents. All-cause mortality was 8.0% [95% CI 5.5-10.8, I² =79.1%) at six months and 9.8% [95% CI 6.2-14.0], I² =80.5%) at twelve months, respectively. All-cause mortality was highest in Africa and Asia/Pacific. Overall, 44.1% ([95% CI 36.1-52.2], I² =91.7%) of patients recovered their LV function within six months and 58.7% ([95% CI 48.1-68.9], I² =75.8%) within twelve months, respectively. Europe and North America reported the highest prevalence of LV recovery. Frequent prescription of beta-blocker, ACE-I/ARB and bromocriptine/cabergoline were associated with significantly lower all-cause mortality and better LV recovery.

CONCLUSION

We identified significant global differences in six- and twelve-month outcomes in women with PPCM. Frequent prescription of guideline-directed heart failure therapy was associated with better LV recovery and lower all-cause mortality. Timely initiation and up-titration of heart failure therapy should therefore be strongly encouraged to improve outcome in PPCM. This article is protected by copyright. All rights reserved.

Comparative analysis of LVAD patients in regard of ischaemic or idiopathic cardiomyopathy: A propensity-score analysis of EUROMACS data

BACKGROUND

Despite recent advances in management of patients with advanced heart failure, mortality remains high. Aim of this study was to compare impact of different aetiology of ischaemic and idiopathic cardiomyopathy on early outcomes and long-term survival of patients after left ventricular assist device implantation.

METHODS

European Registry for Patients with Mechanical Circulatory Support (EUROMACS) gathers clinical data and follow-up parameters of LVAD recipients. Patients enrolled in the EUROMACS registry with primary diagnosis of either ischaemic (n = 1190) or idiopathic (n = 812) cardiomyopathy were included. Primary Endpoints were early mortality as well as long-term survival. Secondary endpoint were major postoperative adverse events, such as need for rethoracotomy. Additionally, a propensity-score matching analysis was performed for patients with ischaemic (n = 509) and idiopathic (n = 509) cardiomyopathy.

RESULTS

In terms of basic demographics and baseline parameters the two groups significantly differed as expected before propensity-score matching due to different aetiology of cardiomyopathy. Seven-day (52 (4.4%) versus 18 (2.2%); p = 0.009), 30-day (153 (12.9%) versus 73 (9.0%); p = 0.008) and in-hospital mortality (253 (19.7%) versus 123 (15.1%); p = 0.009) were significantly lower in the idiopathic cardiomyopathy group compared to the ischaemic cardiomyopathy group, whereas after propensity-score matching 30-day (p = 0.169) was comparable and in-hospital mortality (p = 0.051) was almost significant. Kaplan-Meier survival analysis revealed no significant difference in regard of long-term survival after propensity-score matching (Breslow-test p = 0.161 and LogRank-test p = 0.113).

CONCLUSION

Though patients with ischaemic and idiopathic cardiomyopathy suffer from different cardiomyopathy aetiologies, 30-day-mortality and long-term survival of both groups were similar leading to the conclusion that covariates predominately influence mortality and survival of ischaemic and idiopathic cardiomyopathies.

Physiology of Continuous-Flow Left Ventricular Assist Device Therapy

The expanding use of continuous-flow left ventricular assist devices (CF-LVADs) for end-stage heart failure warrants familiarity with the physiologic interaction of the device with the native circulation. Contemporary devices utilize predominantly centrifugal flow and, to a lesser extent, axial flow rotors that vary with respect to their intrinsic flow characteristics. Flow can be manipulated with adjustments to preload and afterload as in the native heart, and ascertainment of the predicted effects is provided by differential pressure-flow (H-Q) curves or loops. Valvular heart disease, especially aortic regurgitation, may significantly affect adequacy of mechanical support. In contrast, atrioventricular and ventriculoventricular timing is of less certain significance. Although beneficial effects of device therapy are typically seen due to enhanced distal perfusion, unloading of the left ventricle and atrium, and amelioration of secondary pulmonary hypertension, negative effects of CF-LVAD therapy on right ventricular filling and function, through right-sided loading and septal interaction, can make optimization challenging. Additionally, a lack of pulsatile energy provided by CF-LVAD therapy has physiologic consequences for end-organ function and may be responsible for a series of adverse effects. Rheological effects of intravascular pumps, especially shear stress exposure, result in platelet activation and hemolysis, which may result in both thrombotic and hemorrhagic consequences. Development of novel solutions for untoward device-circulatory interactions will facilitate hemodynamic support while mitigating adverse events. © 2021 American Physiological Society. Compr Physiol 12:1-37, 2021.