Defining levels of care in cardiogenic shock.

Background: Expert opinion and professional society statements have called for multi-tier care systems for the management of cardiogenic shock (CS). However, little is known about how to pragmatically define centers with different levels of care (LOC) for CS. Methods: Eleven of 23 hospitals within our healthcare system sharing a common electronic health record were classified as different LOC according to their highest mechanical circulatory support (MCS) capabilities: Level 1 (L-1)-durable left ventricular assist device, Level 1A (L-1A)-extracorporeal membrane oxygenation, Level 2 (L-2)-intra-aortic balloon pump and percutaneous ventricular assist device; and Level 3 (L-3)-no MCS. All adult patients treated for CS (International Classification of Diseases, ICD-10 code R57.0) between 2016 and 2022 were included. Etiologies of CS were identified using associated diagnostic codes. Management strategies and outcomes across LOC were compared. Results: Higher LOC centers had higher volumes: L-1 (n = 1): 2,831 patients, L-1A (n = 4): 3,452, L-2 (n = 1): 340, and L-3 (n = 5): 780. Emergency room admissions were more common in lower LOC (96% at L-3 vs. 46% L-1; p < 0.001), while hospital transfers were predominant at higher LOC (40% at L-1 vs. 2.7% at L-3; p < 0.001). Men comprised 61% of the cohort. Patients were younger in the higher LOC [69 (60-78) years at L-1 vs. 77 (67-85) years at L-3; p < 0.001]. Patients with acute myocardial infarction (AMI)-CS and acute heart failure (AHF)-CS were concentrated in higher LOC centers while other etiologies of CS were more common in L-2 and L-3 (p < 0.001). Cardiac arrest on admission was more prevalent in lower LOC centers (L-1: 2.8% vs. L-3: 12.1%; p < 0.001). Patients with AMI-CS received more percutaneous coronary intervention in lower LOC (51% L-2 vs. 29% L-1; p < 0.01) but more coronary arterial bypass graft surgery at higher LOC (L-1: 42% vs. L-1A: 23%; p < 0.001). MCS use was consistent across levels for AMI-CS but was more frequent in higher LOC for AHF-CS patients (L-1: 28% vs. L-2: 10%; p < 0.001). Despite increasing in-hospital mortality with decreasing LOC, no significant difference was seen after multivariable adjustment. Conclusion: This is the first report describing a pragmatic classification of LOC for CS which, based on MCS capabilities, can discriminate between centers with distinct demographics, practice patterns, and outcomes. This classification may serve as the basis for future research and the creation of CS systems of care.

Surface mapping demonstrates compatibility of implantable loop monitor with a continuous-flow left ventricular assist device.

Syncope in patients with continuous-flow left ventricular assist device may be associated with arrhythmia and difficult to determine without an implantable cardioverter defibrillator. We present a patient with continuous-flow left ventricular assist device, no implantable cardioverter defibrillator, and recurrent syncope. An implantable loop recorder was successfully implanted with surface mapping without noise interference.

Fibrosis in Hypertrophic Cardiomyopathy Patients With and Without Sarcomere Gene Mutations.

BACKGROUND: Patients with hypertrophic cardiomyopathy (HCM) and an identified sarcomere mutation have worse outcomes than those without though the underlying mechanism is incompletely understood. The presence of replacement fibrosis measured by late gadolinium enhancement (LGE) and diffuse fibrosis measured by extracellular volume (ECV) using cardiac magnetic resonance imaging (CMR) are associated with ventricular arrhythmias and cardiac mortality. We aimed to associate these two forms of fibrosis with identified sarcomere mutations. METHODS AND RESULTS: Three hundred and thirty-six (336) patients with HCM underwent CMR at a single quaternary referral centre between January 2012 and February 2017. Genetic testing was performed in 73 of these patients, yielding an identified sarcomeric mutation in 29 (G+), no mutation in 39 (G-), and a variant of unknown significance (VUS) in five. LGE was more prevalent in G+ compared to G- patients (86 vs. 56%, OR 4.3, p=0.01) and was more extensive (7.5±5.5% of left ventricular [LV] mass vs. 3.0±3.0%, p<0.001). Global ECV from myocardial segments excluding LGE was similar among both groups (26.9±2.9 vs. 25.6±2.8%, p=0.46). However, in G+ patients ECV was greater in the hypertrophied regions of the basal anteroseptum (30.2±7.0 vs. 26.8±3.6%, p=0.004) and basal inferoseptum (28.1±4.3 vs. 26.2±2.9%, p=0.005). CONCLUSIONS: Genotyped HCM patients with an identified sarcomere mutation have greater LGE and greater regional, but not global, ECV than HCM patients without an identified mutation. This difference in fibrosis may contribute to worse outcomes in patients with an identified HCM mutation.

COVID-19 in recent heart transplant recipients: Clinicopathologic features and early outcomes.

BACKGROUND: The impact of COVID-19 on heart transplant (HTx) recipients remains unclear, particularly in the early post-transplant period. METHODS: We share novel insights from our experience in five HTx patients with COVID-19 (three within 2 months post-transplant) from our institution at the epicenter of the pandemic. RESULTS: All five exhibited moderate (requiring hospitalization, n = 3) or severe (requiring ICU and/or mechanical ventilation, n = 2) illness. Both cases with severe illness were transplanted approximately 6 weeks before presentation and acquired COVID-19 through community spread. All five patients were on immunosuppressive therapy with mycophenolate mofetil (MMF) and tacrolimus, and three that were transplanted within the prior 2 months were additionally on prednisone. The two cases with severe illness had profound lymphopenia with markedly elevated C-reactive protein, procalcitonin, and ferritin. All had bilateral ground-glass opacities on chest imaging. MMF was discontinued in all five, and both severe cases received convalescent plasma. All three recent transplants underwent routine endomyocardial biopsies, revealing mild (n = 1) or no acute cellular rejection (n = 2), and no visible viral particles on electron microscopy. Within 30 days of admission, the two cases with severe illness remain hospitalized but have clinically improved, while the other three have been discharged. CONCLUSIONS: COVID-19 appears to negatively impact outcomes early after heart transplantation.

Myocardial tissue characterization by gadolinium-enhanced cardiac magnetic resonance imaging for risk stratification of adverse events in hypertrophic cardiomyopathy.

Hypertrophic cardiomyopathy (HCM) is a genetic cardiomyopathy with a wide spectrum of clinical manifestations. Patients can be asymptomatic or suffer major adverse events including sudden cardiac death, ventricular arrhythmias, and heart failure. Identification of individuals with HCM who are at risk for these complications remains challenging. While echocardiography remains the mainstay of diagnostic evaluation, cardiac magnetic resonance imaging (CMR) is an important adjunctive diagnostic modality with emerging applications for risk-stratification of adverse events in the HCM population. Although not included in current guidelines for HCM management, there is increasing evidence to support the use of CMR for routine prognostic assessment of HCM patients. In this review we discuss the use of CMR techniques, including late gadolinium enhancement, T1 mapping, and quantification of extracellular volume fraction, for the risk stratification of three major adverse events in HCM: sudden cardiac death, ventricular arrhythmias, and congestive heart failure.

The use of a durable right ventricular assist device for isolated right ventricular failure due to combined pre- and postcapillary pulmonary hypertension.

Patients with isolated right ventricular (RV) failure have poor outcomes and minimal treatment options. We report a case where a durable RV assist device (RVAD) was implanted for end-stage RV failure from combined pre- and postcapillary pulmonary hypertension (PH) due in part to chronic thromboembolic PH using a temporary percutaneous RVAD as a bridging strategy. While the patient ultimately died from non-cardiovascular causes, there was significant improvement in markers of cardiogenic shock and hemodynamic RV function parameters without adverse effects from increased pulmonary artery pressures. More research is needed to identify an appropriate long-term mechanical support strategy for this patient population.

Relation of the Myocardial Contraction Fraction, as Calculated from M-Mode Echocardiography, With Incident Heart Failure, Atherosclerotic Cardiovascular Disease and Mortality (Results from the Cardiovascular Health Study).

We evaluated the association between 2-dimensional (2D) echocardiography (echo)-determined myocardial contraction fraction (MCF) and adverse cardiovascular outcomes including incident heart failure (HF), atherosclerotic cardiovascular disease (ASCVD), and mortality. The MCF, the ratio of left ventricular (LV) stroke volume (SV) to myocardial volume (MV), is a volumetric measure of myocardial shortening that can distinguish pathologic from physiological hypertrophy. Using 2D echo-guided M-mode data from the Cardiovascular Health Study, we calculated MCF in subjects with LV ejection fraction (EF) ≥55% and used Cox models to evaluate its association with incident HF, ASCVD, and all-cause mortality after adjusting for clinical and echo parameters. We assessed whether log2(SV) and log2(MV) were consistent with the expected 1:-1 ratio used in the definition of MCF. Among 2,147 participants (age 72 ± 5 years), average MCF was 59 ± 13%. After controlling for clinical and echo variables, each 10% absolute increment in MCF was associated with lower risk of HF (hazard ratio [HR] 0.88; 95% confidence interval [CI] 0.82, 0.94), ASCVD (HR 0.90; 95% CI 0.85, 0.95), and death (HR 0.93; 95% CI 0.89, 0.97). Moreover, the MCF was still significantly associated with ASCVD and mortality, but not HF, after adjustment for percent-predicted LV mass. Significant departure from the 1:-1 ratio was not observed for ASCVD or death, but did occur for HF, driven by a stronger association for MV than SV. In conclusion, among older adults without CVD or low LV ejection fraction, 2D echo-guided M-mode-derived MCF was independently associated with lower risk of adverse cardiovascular outcomes, but this ratiometric index may not capture the full relation that is apparent when its components are modeled separately in the case of HF.

Cardiovascular effects of hemoglobin response in patients receiving epoetin alfa and oral iron in heart failure with a preserved ejection fraction.

BACKGROUND: Previous data from a recently conducted prospective, single blind randomized clinical trial among community dwelling older patients with heart failure with a preserved ejection fraction (HFPEF) and anemia randomized to treatment with epoetin alfa (erythropoiesis-stimulating agents, ESA) vs. placebo did not demonstrate significant benefits of therapy regarding left ventricular (LV) structure, functional capacity, or quality of life (QOL). However, several patients randomized to the treatment arm were non-responders with a suboptimal increase in hemoglobin. All patients in the trial also received oral ferrous gluconate, which could have contributed to increases in hemoglobin observed in those receiving placebo. Accordingly, we performed an analysis separating patients into responders vs. non-responders in order to determine if measured improvement in anemia would have any effect on clinical endpoints. METHODS: A total of 56 patients (age 77 ± 11 years, 68% female) were recruited who had anemia defined as a hemoglobin of ≤ 12 g/dL (average, 10.4 ± 1 g/dL) with HFPEF defined as having NHANES-CHF (National Health And Nutrition Examination Survey: Congestive Heart Failure) criteria score of ≥ 3 and an ejection fraction of > 40% (average EF = 63% ± 15%). Patients were randomly allocated to receive either ESA and ferrous gluconate or ferrous gluconate only. In this analysis, a responder was defined as a patient with an increase of 1 g/dL in the first 4 weeks of the trial. RESULTS: Nineteen subjects were classified as responders compared to 33 non-responders. While the average hemoglobin increased significantly at the end of 6 months for responders (1.8 ± 0.3 vs. 0.8 ± 0.2 g/dL, P = 0.004), 50% of the subjects assigned to ESA were non-responders. Left ventricular function including ejection fraction (P = 0.32) and end diastolic volume (P = 0.59) was unchanged in responders compared to non-responders. Responders also showed no significant improvements in New York Heart Association (NYHA) class, Six Minute Walk Test (6 MWT) and peak VO2. Though QOL improved significantly within each group, there was no difference between the two. CONCLUSIONS: A significant hemoglobin response to anemia treatment with ESA and oral iron does not lead to differences in LV remodeling, functional status, or QOL. Additionally, a significant percent of older adults with HFPEF and anemia do not respond to ESA therapy. Given the results of this small trial, it appears as though using objective improvements in anemia as a marker in older adult subjects with HFPEF does not have significant clinical utility.