Multimodality Imaging in the Evaluation and Prognostication of Cardiac Amyloidosis

Cardiac amyloidosis (CA) is an infiltrative cardiomyopathy resulting from deposition of misfolded immunoglobulin light chains (AL-CA) or transthyretin (ATTR-CA) proteins in the myocardium. Survival varies between the different subtypes of amyloidosis and degree of cardiac involvement, but accurate diagnosis is essential to ensure initiation of therapeutic interventions that may slow or potentially prevent morbidity and mortality in these patients. As there are now effective treatment options for CA, identifying underlying disease pathogenesis is crucial and can be guided by multimodality imaging techniques such as echocardiography, magnetic resonance imaging, and nuclear scanning modalities. However, as use of cardiac imaging is becoming more widespread, understanding optimal applications and potential shortcomings is increasingly important. Additionally, certain imaging modalities can provide prognostic information and may affect treatment planning. In patients whom imaging remains non-diagnostic, tissue biopsy, specifically endomyocardial biopsy, continues to play an essential role and can facilitate accurate and timely diagnosis such that appropriate treatment can be started. In this review, we examine the multimodality imaging approach to the diagnosis of CA with particular emphasis on the prognostic utility and limitations of each imaging modality. We also discuss how imaging can guide the decision to pursue tissue biopsy for timely diagnosis of CA.</jats:p

Abstract 16784: Under-Enrollment of Real-World Heart Failure With Preserved Ejection Fraction Patients in Major HFpEF Clinical Trials

Introduction: Inclusion criteria for enrollment in HFpEF clinical trials vary considerably and often exclude patients with co-morbidities such as obesity. We tested the hypotheses that: 1) a large number of patients with clinical and hemodynamic evidence of HFpEF are excluded from major HFpEF clinical trials; and 2) there is no difference in clinical outcomes between patients excluded versus those who met enrollment criteria by evaluating reasons for exclusion from HFpEF clinical trials and comparing clinical outcomes in a real-world HFpEF cohort. Methods: Patients referred to the Johns Hopkins HFpEF Clinic with clinical and hemodynamic evidence of HFpEF (pulmonary capillary wedge pressure [PCWP] ≥ 12 mmHg on a loop diuretic or PCWP ≥ 15 mmHg) were assessed for inclusion into 4 major HFpEF trials (TOPCAT, I-PRESERVE, PARAGON-HF, and RELAX). Cumulative hazard of HF hospitalization or death at 2 years from index clinic visit was compared between patients included and excluded by each trial. Results: Of 132 HFpEF patients, the median PCWP was 19 mmHg (IQR: 15-22 mmHg). Forty-four (33%) of patients met enrollment criteria for TOPCAT, 39 (29%) for I-PRESERVE, 21 (16%) for PARAGON-HF, and 50 (38%) for RELAX. The top 5 criteria that would have excluded patients included low natriuretic peptide level, obesity, elevated blood pressure, young age, and low hemoglobin (Figure 1A) . There was no difference in HF burden (hospitalizations, diuretic dosing, or NYHA class), or in clinical outcomes including HF hospitalization or death between patients who did or did not meet inclusion criteria for each clinical trial (Figure 1B ). Conclusion: We demonstrate that in a real-world cohort of hemodynamically-proven HFpEF few patients would have met criteria for enrollment in major HFpEF clinical trials, yet HF burden and outcomes were no different. Given the lack of proven therapies in HFpEF, consideration should be given to unifying and broadening enrollment criteria in HFpEF clinical trials. </jats:p