Double Trouble: A Case Of Combined Amyloid And Ischemic Cardiomyopathy

Abstract

Background The management of concurrent cardiac amyloidosis (CA) and ischemic cardiomyopathy (ICM) is not well established due to the rarity of this phenomenon. We present a case of mixed cardiomyopathy with challenging clinical decision-making. Case A 76-year-old African American woman with hypertension, diabetes, and longstanding carpal tunnel syndrome presented with progressive dyspnea and was found to have decompensated heart failure attributable to a new cardiomyopathy. Initial workup revealed left ventricular ejection fraction (LVEF) of 20% and severe triple vessel coronary artery disease. Echocardiogram also demonstrated an apical-sparing strain pattern (Figure 1A) prompted concern for coexisting CA given her demographic and carpal tunnel history. A cardiac magnetic resonance (CMR) raised further concern for CA given restrictive cardiomyopathy, pericardial effusion, and characteristic late gadolinium enhancement (Figure 1B and 1C). Ultimately, transthyretin CA (ATTR) was confirmed with a positive technetium-99m-Pyrophosphate Scintigraphy (PYP) scan (Figure 1D) paired with normal serum immunofixation electrophoresis. She was evaluated by cardiothoracic surgery but deemed a prohibitively high-risk candidate for CABG due to her advanced age, ATTR diagnosis, and significant systolic dysfunction. Instead, she was diuresed and started on guideline-directed medical therapy, which she tolerated unusually well despite her diagnosis of ATTR. Using Impella CP for temporary mechanical circulatory support, she underwent high-risk percutaneous coronary intervention to the distal left main artery extending into the proximal left circumflex. She was discharged on dual antiplatelet therapy. During outpatient follow-up in the Multidisciplinary CA Clinic, genetic testing revealed a pathogenic V122I mutation indicative of hereditary ATTR. She was started on tafamidis after nerve conduction studies did not demonstrate neuropathy. The combination of guideline-directed medical therapy, successful percutaneous revascularization, and ATTR-directed treatment resulted in remarkable improvement (NYHA Class II, LVEF 50% from NYHA IV, LVEF 20%). Conclusion Further investigation is needed to define optimal treatment strategies in patients with coexisting ischemic and amyloid cardiomyopathy. Until then, a multidisciplinary approach must be utilized to individualize the care of such patients. The management of concurrent cardiac amyloidosis (CA) and ischemic cardiomyopathy (ICM) is not well established due to the rarity of this phenomenon. We present a case of mixed cardiomyopathy with challenging clinical decision-making. A 76-year-old African American woman with hypertension, diabetes, and longstanding carpal tunnel syndrome presented with progressive dyspnea and was found to have decompensated heart failure attributable to a new cardiomyopathy. Initial workup revealed left ventricular ejection fraction (LVEF) of 20% and severe triple vessel coronary artery disease. Echocardiogram also demonstrated an apical-sparing strain pattern (Figure 1A) prompted concern for coexisting CA given her demographic and carpal tunnel history. A cardiac magnetic resonance (CMR) raised further concern for CA given restrictive cardiomyopathy, pericardial effusion, and characteristic late gadolinium enhancement (Figure 1B and 1C). Ultimately, transthyretin CA (ATTR) was confirmed with a positive technetium-99m-Pyrophosphate Scintigraphy (PYP) scan (Figure 1D) paired with normal serum immunofixation electrophoresis. She was evaluated by cardiothoracic surgery but deemed a prohibitively high-risk candidate for CABG due to her advanced age, ATTR diagnosis, and significant systolic dysfunction. Instead, she was diuresed and started on guideline-directed medical therapy, which she tolerated unusually well despite her diagnosis of ATTR. Using Impella CP for temporary mechanical circulatory support, she underwent high-risk percutaneous coronary intervention to the distal left main artery extending into the proximal left circumflex. She was discharged on dual antiplatelet therapy. During outpatient follow-up in the Multidisciplinary CA Clinic, genetic testing revealed a pathogenic V122I mutation indicative of hereditary ATTR. She was started on tafamidis after nerve conduction studies did not demonstrate neuropathy. The combination of guideline-directed medical therapy, successful percutaneous revascularization, and ATTR-directed treatment resulted in remarkable improvement (NYHA Class II, LVEF 50% from NYHA IV, LVEF 20%). Further investigation is needed to define optimal treatment strategies in patients with coexisting ischemic and amyloid cardiomyopathy. Until then, a multidisciplinary approach must be utilized to individualize the care of such patients.