Outcomes of Durable Mechanical Circulatory Support in Myocarditis: Analysis of the International Society for Heart and Lung Transplantation Registry for Mechanically Assisted Circulatory Support Registry.

Myocarditis can be refractory to medical therapy and require durable mechanical circulatory support (MCS). The characteristics and outcomes of these patients are not known. We identified all patients with clinically-diagnosed or pathology-proven myocarditis who underwent mechanical circulatory support in the International Society for Heart and Lung Transplantation Registry for Mechanically Assisted Circulatory Support registry (2013-2016). The characteristics and outcomes of these patients were compared to those of patients with nonischemic cardiomyopathy (NICM). Out of 14,062 patients in the registry, 180 (1.2%) had myocarditis and 6,602 (46.9%) had NICM. Among patients with myocarditis, duration of heart failure was <1 month in 22%, 1-12 months in 22.6%, and >1 year in 55.4%. Compared with NICM, patients with myocarditis were younger (45 vs. 52 years, P < 0.001) and were more often implanted with Interagency Registry for Mechanically Assisted Circulatory Support profile 1 (30% vs. 15%, P < 0.001). Biventricular mechanical support (biventricular ventricular assist device [BIVAD] or total artificial heart) was implanted more frequently in myocarditis (18% vs. 6.7%, P < 0.001). Overall postimplant survival was not different between myocarditis and NICM (left ventricular assist device: P = 0.27, BIVAD: P = 0.50). The proportion of myocarditis patients that have recovered by 12 months postimplant was significantly higher in myocarditis compared to that of NICM (5% vs. 1.7%, P = 0.0003). Adverse events (bleeding, infection, and neurologic dysfunction) were all lower in the myocarditis than NICM. In conclusion, although myocarditis patients who receive durable MCS are sicker preoperatively with higher needs for biventricular MCS, their overall MCS survival is noninferior to NICM. Patients who received MCS for myocarditis are more likely than NICM to have MCS explanted due to recovery, however, the absolute rates of recovery were low.

LVAD Vasculitis Case Series: Suggestion of a New Fatal LVAD-Related Phenomenon.

Left ventricular assist devices (LVADs) are surgically implanted mechanical devices indicated for patients with advanced heart failure and are known to come with several complications. Here we present a case series, and review 1 documented report, of LVAD vasculitis, a presumed new LVAD immune/humoral related phenomenon. (Level of Difficulty: Advanced.).

Relation of Pretransplant Peak Oxygen Consumption to Outcomes After Heart Transplantation.

Peak exercise oxygen consumption (pVO2) is an important predictor of prognosis in patients with heart failure (HF). The association between pretransplant pVO2 and post-transplantation outcomes in HF patients has not been previously studied. We identified adult OHT recipients with available pVO2 in the United Network for Organ Sharing registry (2000 to 2015). Patients were divided into 3 categories using Weber classification: class B (pVO2 16 to 20 ml/kg/min), class C (pVO2 10 to 16 ml/kg/min), and class D (pVO2 <10 ml/kg/min). Postoperative outcomes (mortality, renal failure, rejection) were compared between the groups. A total of 9,623 patients were included in this analysis; the mean age was 54 ± 11 years, 74% were male, 75% were white and 59% had nonischemic etiology of HF. The mean pVO2 was 11.7 ± 3.6 ml/kg/min: 1,202 (12.5%) in class B, 6,055 (62.9%) in class C, and 2,366 (24.6%) were in class D. At a median follow-up of 6.1 years, 2,730 (28.4%) died. Post-transplantation survival decreased with decreasing pVO2; 1 and 5-year survival: B (92%, 80%), C (90%, 79%), and D (87%, 75%), p <0.001 by log-rank. After multiple adjustments, patients in class D had significantly higher post-transplantation mortality compared with class C (Hazard Ratio (HR) 1.21 [1.03 to 1.43], p = 0.02). When analyzed as a continuous variable, each 1 ml/kg/min increase in pVO2 was associated with 2% decrease in mortality during follow-up (adjusted HR 0.98 [0.96 to 0.99], p <0.001). Patients in class D had significantly prolonged (>14 days) hospitalization (adjusted Odds Ratio (OR) 1.42 [1.20 to 1.68], p <0.001) and a trend toward increased need for dialysis (adjusted OR 1.36 [1.00 to 1.84], p = 0.05) compared with patients in class B. In this large cohort, lower pretransplant pVO2 was associated with greater mortality and morbidity after OHT. These results suggest that earlier transplantation might improve post-transplantation outcomes in advanced HF patients.

HeartMate II pump exchange with HeartMate III implantation to the descending aorta.

Removal of the HeartMate II left ventricular assist device (LVAD) usually requires a sternotomy. We report a case of HeartMate III LVAD implantation to the descending aorta via a left thoracotomy while leaving most of the HeartMate II device in place to avoid redo-sternotomy.

Myocarditis and cardiomyopathy.

PURPOSE OF REVIEW: The aim of this study is to summarize the literature describing the pathogenesis, diagnosis and management of cardiomyopathy related to myocarditis. RECENT FINDINGS: Myocarditis has a variety of causes and a heterogeneous clinical presentation with potentially life-threatening complications. About one-third of patients will develop a dilated cardiomyopathy and the pathogenesis is a multiphase, mutlicompartment process that involves immune activation, including innate immune system triggered proinflammatory cytokines and autoantibodies. In recent years, diagnosis has been aided by advancements in cardiac MRI, and in particular T1 and T2 mapping sequences. In certain clinical situations, endomyocardial biopsy (EMB) should be performed, with consideration of left ventricular sampling, for an accurate diagnosis that may aid treatment and prognostication. SUMMARY: Although overall myocarditis accounts for a minority of cardiomyopathy and heart failure presentations, the clinical presentation is variable and the pathophysiology of myocardial damage is unique. Cardiac MRI has significantly improved diagnostic abilities, but endomyocardial biopsy remains the gold standard. However, current treatment strategies are still focused on routine heart failure pharmacotherapies and supportive care or cardiac transplantation/mechanical support for those with end-stage heart failure.

Heart Transplantation in Giant Cell Myocarditis: Analysis of the United Network for Organ Sharing Registry.

BACKGROUND: Giant cell myocarditis (GCM) is a lethal, rapidly progressive disease, for which heart transplantation is the treatment of choice. We sought to describe the characteristics and outcomes of patients with GCM who undergo heart transplantation. METHODS AND RESULTS: We used the United Network for Organ Sharing thoracic organ transplantation registry to identify adults with GCM as the primary diagnosis and compared their characteristics and outcomes with patients who underwent transplantation for other types of myocarditis and for idiopathic dilated cardiomyopathy (IDCMP). A total of 32 patients with GCM were compared with 219 patients with myocarditis and 14,221 patients with IDCMP. Median age at listing for GCM was 52 years (interquartile range 40-55 y), and the majority were white (94%), male (63%), and listed as 1A (44%). Biventricular assist devices were used more frequently in GCM compared with IDCMP (31% vs 2%; P < .001). After transplantation, there were no statistically significant differences among GCM, myocarditis, and IDCMP patients regarding pacemaker implantation, dialysis initiation, or stroke rate. GCM patients had increased risk of acute rejection compared with IDCMP patients (16% vs 5.0%; P = .021) but no difference in rehospitalization for rejection among the 3 etiologies (P = .88). The cumulative survivals for GCM patients at 1, 5, and 10 years were 94%, 82%, and 68%, respectively, which was similar to the other etiologies (P = .11). CONCLUSIONS: Compared with patients with IDCMP, those with GCM present more acutely and have significantly higher utilization of biventricular mechanical circulatory support. Despite higher rates of early rejection, post-transplantation survival of patients with GCM was similar to that of other myocarditides and IDCMP.

Left Ventricular Assist Devices or Inotropes for Decreasing Pulmonary Vascular Resistance in Patients with Pulmonary Hypertension Listed for Heart Transplantation.

BACKGROUND: Fixed pulmonary hypertension is common in patients with advanced heart failure and is a contraindication for heart transplantation. Left ventricular assist devices (LVAD) and inotropes have been used to reduce pulmonary vascular resistance (PVR) and allow transplantation. However, little is known about the efficacy of this strategy. METHODS: We queried the United Network for Organ Sharing registry for all adult patients (age ≥18 years) listed for primary heart transplantation (2008-2014) with PVR of >5 wood units (WU) or transpulmonary gradient >16 mmHg who were treated with LVAD or IV inotropes as status 1a, 1b, or 7. We compared waitlist mortality/delisting and absolute changes in hemodynamics between listing and transplantation. RESULTS: Of 18,009 patients listed during the study period, 1016 were included in the analysis (393 LVAD, 623 inotropes), with a mean age of 52.9 ± 11.6 years, 74% male, and 38% had ischemic etiology. Mean PVR was 5.7 ± 2.4 WU and transpulmonary pressure gradient 19.3 ± 5.3 mmHg. Compared with the inotrope group, LVAD patients were more likely listed as status 1A (32.8% vs 18.1%, P < .001), had lower PVR (5.3 WU vs 5.9 WU, P = .001), and higher cardiac output (4.1 vs 3.6 L/min, P < .001). After a mean of 239 days, PVR decreased by 1.71 WU in the LVAD group vs 1.85 WU in the inotrope group (P = .52). PVR normalization (<2.5 WU) occurred at similar rates among those treated with inotropes and LVAD (30.7% vs 35.6%, P = .228). Waitlist mortality was similar between LVAD and inotropes (adjusted P = .837). Absolute PVR and transpulmonary pressure gradient reductions correlated with time on the waitlist (P < .001 for both comparisons). CONCLUSION: Only about one-third of patients with fixed pulmonary hypertension achieve normalization of PVR before transplant with either LVAD or inotropes. Similar waitlist mortality was observed among patients bridged with either strategy.

Characteristics and Outcomes of Patients With Myocarditis Listed for Heart Transplantation.

BACKGROUND: Myocarditis can cause dilated cardiomyopathy resulting in end-stage heart failure requiring advanced therapies. There is little contemporary information on the clinical progression, need for mechanical circulatory support, and outcomes of orthotopic heart transplantation of these patients. METHODS AND RESULTS: We queried the UNOS database (United Network for Organ Sharing) for all adults listed for orthotopic heart transplantation (2000-2015) with a listed diagnosis of myocarditis. Comparative and survival analyses were performed. Of 45 941 adults listed for orthotopic heart transplantation during this period, we identified 299 patients (0.7%) with the diagnosis of myocarditis. Compared with patients with nonischemic cardiomyopathy (NICM) and ischemic cardiomyopathy (ICM), myocarditis patients were younger (myocarditis 43.4±14.2 years, NICM 49.8±12.4 years, and ICM 57.5±8.0 years; P<0.001) and more frequently listed as status 1A (myocarditis 44% versus NICM 21% versus ICM 21%; P<0.001), with significantly higher need for mechanical ventilation (myocarditis 11% versus NICM 2% versus ICM 4%; P<0.001), biventricular mechanical circulatory support (myocarditis 19% versus NICM 2%, versus ICM 2%; P<0.001), and extracoroporeal membrane oxygenation (myocarditis 5% versus NICM 0.4% versus ICM 1%; P<0.001). Additionally, patients with myocarditis had higher likelihood of delisting for clinical improvement (hazard ratio, 2.49 [95% confidence interval, 1.63-3.79] versus ICM and hazard ratio, 2.12 [95% confidence interval, 1.40-3.22] versus NICM; P<0.001). Despite higher allosensitization, patients with myocarditis had similar post-transplant rejection, retransplantation, and survival rates compared with other groups. CONCLUSIONS: Patients with the diagnosis of myocarditis listed for orthotopic heart transplantation are younger, sicker, and recover more frequently but require more biventricular mechanical circulatory support. Heart transplantation survival is comparable to that of patients with other types of heart failure.

Model for end-stage liver disease excluding international normalized ratio (MELD-XI) score predicts heart transplant outcomes: Evidence from the registry of the United Network for Organ Sharing.

BACKGROUND: Hepato-renal function is a valuable predictor of success after left ventricular assist device therapy and heart transplantation. Hence, we analyzed the importance of the Model for End-stage Liver Disease excluding international normalized ratio (MELD-XI) score to outcomes after heart transplant. METHODS: Adults undergoing heart transplant from the United Network for Organ Sharing (UNOS) database were identified (1994 to 2014). Individual MELD-XI scores were calculated; patients were stratified by MELD-XI quartiles (Q1 to Q4). Multivariate logistic regression and the Cox proportional hazard model were implemented to determine any association between MELD-XI scores, survival and other outcomes. RESULTS: From 39,711 patients undergoing OHT during the study period, MELD-XI score [median 10.7 (interquartile range 7.0 to 14.4)] was calculated for 36,005 patients (76% male and 75% white, 34% Status 1A). Higher MELD-XI scores had higher rates of pre-transplant extracorporeal membrane oxygenation, intra-aortic balloon pump, inotrope use and mechanical ventilation (p < 0.001 for all). Adjusted long-term mortality (median follow-up 8.1 years) was associated with MELD-XI score (hazard ratio [HR] 1.021 [1.016 to 1.026], p < 0.001). The highest MELD-XI quartile was associated with an HR 1.364 [1.255 to 1.482] risk of mortality compared with Q1. MELD-XI score was also associated with increased post-transplant infections (adjusted HR Q4 vs Q1: 1.364 [1.153 to 1.614], p < 0.001), stroke (adjusted HR Q4 vs Q1: 1.410 [1.074 to 1.852], p = 0.013), dialysis (adjusted HR Q4 vs Q1: 3.982 [3.386 to 4.683], p < 0.001), rejection (adjusted HR Q4 vs Q1: 1.519 [1.286 to 1.795], p = 0.003) and prolonged hospitalization (adjusted HR Q4 vs Q1: 1.635 [1.429 to 1.871], p < 0.001). CONCLUSION: Hepato-renal dysfunction, measured with MELD-XI score, predicts morbidity and mortality in patients undergoing orthotopic heart transplantation. Etiology of hepato-renal dysfunction should be sought and treated before heart transplantation.