High-risk cardiac surgery as an alternative to transplant or mechanical support in patients with end-stage heart failure

Programmatic approach to patients with advanced ischemic cardiomyopathy: Integrating microaxial support into strategies for the modern era

Patients with advanced ischemic cardiomyopathy manifesting as left ventricular dysfunction exist along a spectrum of severity and risk, and thus decision-making surrounding optimal management is challenging. Treatment pathways can include medical therapy as well as revascularization through percutaneous coronary intervention or coronary artery bypass grafting. Additionally, temporary and durable mechanical circulatory support, as well as heart transplantation, may be optimal for select patients. Given this spectrum of risk and the complexity of treatment pathways, patients may not receive appropriate therapy given their perceived risk, which can lead to sub-satisfactory outcomes. In this review, we discuss the identification of high-risk ischemic cardiomyopathy patients, along with our programmatic approach to patient evaluation and perioperative optimization. We also discuss our strategies for therapeutic decision-making designed to optimize both short- and long-term patient outcomes.

Impact of Previous Conventional Cardiac Surgery on the Clinical Outcomes After Heart Transplantation

The impact of the type, purpose, and timing of prior surgery on heart transplantation (HT) remains unclear. This study investigated the influence of conventional cardiac surgery (PCCS) on HT outcomes. This study analyzed HTs performed between 1999 and 2019 at a single institution. Patients were categorized into two groups: those with and without PCCS. Short-term outcomes, including post-transplant complications and mortality rates, were evaluated. Cox proportional and Kaplan-Meier survival analyses were used to identify risk factors for mortality and assess long-term survival, respectively. Of 368 patients, 29% had PCCS. Patients with PCCS had a higher incidence of post-transplant complications. The in-hospital and 1 year mortality rates were higher in the PCCS group. PCCS and cardiopulmonary bypass time were significant risk factors for 1 year mortality (hazard ratios = 2.485 and 1.005, respectively). The long-term survival rates were lower in the PCCS group, particularly in the first year. In sub-analysis, patients with ischemic cardiomyopathy and PCCS had the poorest outcomes. The era of surgery and timing of PCCS in relation to HT did not significantly impact outcomes. In conclusion, PCCS worsen the HT outcomes, especially in patients with ischemic etiology. However, the timing of PCCS and era of HT did not significantly affect this concern.

Contemporary contribution of cardiac surgery for the treatment of cardiomyopathies and pericardial diseases

Cardiomyopathy refers to a spectrum of heterogeneous myocardial disorders characterized by morphological and structural alterations leading eventually to heart failure, by affecting cardiac filling and/or the cardiac systolic function. Heart transplantation is currently the gold standard surgical treatment for patients with heart failure, with a median survival in adults of 12 years according to international registries. However, the limited available donor pool does not allow its extensive employment. For this reason, mechanical circulatory supports are increasingly used, and in the short term are becoming as possible alternatives to heart transplantation, owing to improved technologies and increased biocompatibility. However, long-term outcomes of mechanical assist devices are still burdened with a high rate of adverse events. Conventional surgical treatments could be still considered as alternatives to heart replacement treatment when tailored both on patient clinical conditions and etiology of cardiac diseases. In particular, among patients affected by ischemic cardiomyopathy, coronary artery bypass grafting has proven to improve survival when associated to optimal medical treatment, and surgical ventricular restoration might be considered as a valid treatment in particular cases. Correction of functional mitral valve regurgitation by mitral annuloplasty, which aims to restore left ventricular geometry, has not demonstrated unambiguous results, and outcomes of this procedure are still controversial. Pericardial pathology becomes of surgical interest when it is responsible for a reduced filling capacity of the heart chambers, which can develop acutely (cardiac tamponade) or chronically (as in the case of constrictive pericarditis). This review focuses on the different surgical approaches that could be adopted to treat patients with heart failure and pericardial diseases.

Temporary mechanical circulatory support prevents the occurrence of a low-output state in high-risk coronary artery bypass grafting: A case series

BACKGROUND

Coronary artery bypass grafting (CABG) is a durable treatment for coronary artery disease. Left ventricular dysfunction (LVD) (a division of cardiothoracic surgery) (ejection fraction < 35%) significantly elevates perioperative risk for patients pursuing surgical revascularization. Periprocedural support with temporary mechanical circulatory support (tMCS) has shown benefit in this patient population.

METHODS

Four patients with ischemic cardiomyopathy and LVD underwent CABG at our institution between 2017 and 2018. Each patient received perioperative ventricular support using a microaxial tMCS device (Impella 5.0®). The occurrence of a postoperative low-output state (LOS) was assessed for as well as postoperative morbidity and mortality, device-specific complications, and tMCS support duration.

RESULTS

All patients survived to device explant without device-related complications. Two patients required reoperation for nondevice-related bleeding. All patients were without an LOS at 24 h postoperatively with cardiac indices of 2.9-3.6 L/min/m² , normalized serum lactate, and vasoactive-inotrope scores of 0-12.0. There was a notably high incidence of acute renal failure (50%), which was observed in patients with preoperative cardiogenic shock. One patient died 10 days after the device explant. Of the three patients that survived to discharge, two were alive at the most recent follow-up. Postoperative device support varied widely (0-500 h).

CONCLUSION

Perioperative tMCS may be a viable strategy for preventing postoperative LOS in high-risk CABG patients with a low complication rate and acceptable morbidity. The application of microaxial tMCS devices in CABG is an area that warrants further investigation to delineate its impact on perioperative outcomes and potentially expand the indications for such devices.

Long-term transplant outcomes of donor hearts with left ventricular dysfunction

OBJECTIVE

Despite small single-center reports demonstrating acceptable outcomes using donor hearts with left ventricular dysfunction, 19% of potential donor hearts are currently unused exclusively because of left ventricular dysfunction. We investigated modern long-term survival of transplanted donor hearts with left ventricular dysfunction using a large, diverse cohort.

METHODS

Using the United Network for Organ Sharing database, we reviewed all adult heart transplants between January 2000 and March 2016. Baseline and postoperative characteristics and Kaplan-Meier survival curves were compared. A covariates-adjusted Cox regression model was developed to estimate post-transplant mortality. To address observed variation in patient profile across donor ejection fraction, a propensity score was built using Cox predictors as covariates in a generalized multiple linear regression model. All the variables in the original Cox model were included. For each recipient, a predicted donor ejection fraction was generated and exported as a new balancing score that was used in a subsequent Cox model. Cubic spline analysis suggested that at most 3 and perhaps no ejection fraction categories were appropriate. Therefore, in 1 Cox model we added donor ejection fraction as a grouped variable (using the spline-directed categories) and in the other as a continuous variable.

RESULTS

A total of 31,712 donor hearts were transplanted during the study period. A total of 742 donor hearts were excluded for no recorded left ventricular ejection fraction, and 20 donor hearts were excluded for left ventricular ejection fraction less than 20%. Donor hearts with reduced left ventricular ejection fraction were from younger donors, more commonly male donors, and donors with lower body mass index than normal donor hearts. Recipients of donor hearts with reduced left ventricular ejection fraction were more likely to be on mechanical ventilation. Kaplan-Meier curves revealed no significant differences in recipient survival up to 15 years of follow-up (P = .694 log-rank test). Cox regression analysis showed that after adjustment for propensity variation, transplant year, and region, ejection fraction had no statistically significant impact on mortality when analyzed as a categoric or continuous variable. Left ventricular ejection fraction at approximately 1 year after transplantation was normal for all groups.

CONCLUSIONS

Carefully selected donor hearts with even markedly diminished left ventricular ejection fraction can be transplanted with long-term survival equivalent to normal donor hearts and therefore should not be excluded from consideration on the basis of depressed left ventricular ejection fraction alone. Functional recovery of even the most impaired donor hearts in this study suggests that studies of left ventricular function in the setting of brain death should be interpreted cautiously.

Surgical ventricular remodeling: should we STICH or not?

PURPOSE OF REVIEW

The surgical management of patients with ischemic cardiomyopathy, especially those with left ventricular ejection fractions less than 20% has historically been controversial. The original trials of surgical revascularization versus medical therapy intentionally excluded those patients with an ejection fraction less than 35%. The significant advances in medical therapy for heart failure over the past 30 years (β-blockade, angiotensin converting enzyme inhibitors, internal cardiac defibrillator and so on) also mandated a reevaluation of the potential benefits of surgical revascularization in this high-risk subset. The purpose of this review is to examine the data from the Surgical Treatment for Ischemic Heart Failure (STICH) trial, initially reported in 2009 and 2011.

RECENT FINDINGS

Recent reports published in 2016 have now clearly defined the role of surgery over medical therapy for these patients. Furthermore, although the benefits of surgical ventricular reconstruction were once questioned by the results of STICH, further analyses identify that an appropriately selected patient who undergoes a technically adequate operation will derive benefit from surgical ventricular reconstruction.

SUMMARY

The conclusions from the various substudies examining STICH trial data now indicate that in surgical candidates with graftable coronary artery disease, surgical revascularization provides a reduction in overall mortality, cardiovascular deaths and hospitalizations, independent of symptoms, baseline left ventricular size or function and surprisingly, regardless of any viability or evidence of inducible ischemia.