Rare Variant of Hereditary Amyloid Transthyretin Cardiomyopathy Secondary to Ser97Tyr Mutation.

Hereditary transthyretin amyloidosis (hATTR) is an autosomal dominant, adult-onset disease that stems from point mutations in the TTR gene encoding the protein transthyretin. The disease is progressive and life-threatening and is associated with amyloid deposits in multiple organs including the heart, kidney, skin, eyes, nervous system, and gastrointestinal tract. Genotypic and phenotypic heterogeneity is a characteristic hallmark of hereditary transthyretin amyloidosis. Herein, we present a rare variant of hATTR cardiomyopathy secondary to Ser97Tyr mutation, having been documented only in a handful of families previously. This case serves as a valuable opportunity to elucidate the clinico-pathogenesis of this disease, highlight the aggressive nature of this genetic mutation (c.290C>A; p.Ser97Tyr), and document the response to the latest advances in treatment currently available.

Endomyocardial biopsy-proven hydroxychloroquine-induced cardiomyopathy in a patient with rheumatoid arthritis.

Hydroxychloroquine is a disease-modifying antirheumatic drug used for various rheumatological conditions. Its long-term use is well-known to have toxic effects on cardiac muscle cells. We present a biopsy-proven case of hydroxychloroquine-induced cardiotoxicity with detailed histopathological and imaging findings. The patient was referred to our heart failure clinic for concerns of reduction in left ventricular ejection fraction despite being on guideline-directed medical therapy. She had been diagnosed with rheumatoid arthritis, pulmonary hypertension and then subsequently heart failure with reduced ejection fraction 5 years ago. The evaluation included right heart catheterisation, cardiac MRI and endomyocardial biopsy. Light and electron microscopy showed myocyte hypertrophy and vacuolar change, abnormal mitochondria, myeloid bodies and curvilinear bodies. These findings were specific for hydroxychloroquine-induced cardiomyopathy. This case highlights the importance of clinical monitoring, early suspicion and consideration of drug-induced toxicities as a culprit for heart failure.

Impact of Biopsy Proven Liver Fibrosis on Patients Undergoing Evaluation and Treatment for Advanced Heart Failure Surgical Therapies.

There is a paucity of data regarding the impact of liver fibrosis on patients with stage D heart failure (HF). We conducted a retrospective study (January 1, 2017 to December 12, 2020) in patients with stage D HF who underwent liver biopsy as part of their advanced HF therapy evaluation. Baseline characteristics and 1-year outcomes were compared between no- or mild-to-moderate-fibrosis (grade 0 to 2) and advanced-fibrosis (grade 3 to 4) groups. Of 519 patients with stage D HF, 136 who underwent liver biopsy (113 [83%] no or mild-to-moderate fibrosis and 23 [17%] advanced fibrosis) were included. A total of 71 patients (52%) received advanced HF therapies (23 heart transplantation, 48 left ventricular assist devices). One-year mortality was higher among patients with advanced fibrosis (52% vs 18%, p <0.001). Further subgroup analysis suggested a trend toward increased 1-year mortality among patients with advanced fibrosis who underwent advanced therapies (37% vs 13%, p = 0.09). There was a trend of lower likelihood of receiving advanced HF therapies in the advanced-fibrosis group, only 1 heart transplantation and 7 left ventricular assist devices, but it did not reach statistical significance (35% vs 56%, p = 0.06). After adjustment for confounders, degree of liver fibrosis was an independent predictor of mortality (odds ratio 6.2; 95% 1.27 to 30.29, p = 0.02). We conclude that advanced liver fibrosis is common among patients with stage D HF who undergo evaluation for advanced HF surgical therapies and significantly increases 1-year mortality. Further larger studies are needed to support our findings.

Loperamide-induced cardiogenic syncope: a case report of a life-threatening presentation of an over-the-counter drug.

Background: Loperamide at supratherapeutic doses can cause cardiac toxicity, presenting as cardiogenic shock, prolonged QT, malignant arrhythmias, or in severe cases sudden cardiac death. Surreptitious loperamide use is difficult to diagnose. We present an interesting case of loperamide use presenting with polymorphic ventricular tachycardia, cardiogenic shock. Case summary: A 25-year-old female presented with multiple syncopal episodes for 12 months with an electrocardiogram showing a Brugada-like pattern for which she underwent implantable cardioverter-defibrillator placement. One day following the procedure, she developed cardiogenic shock and was transferred to our tertiary care centre. Extensive workup was unrevealing. She responded well to supportive management, recovering from shock and was transferred to the floor. Unfortunately, she again developed cardiogenic shock, ultimately leading to cardiac arrest. Given the unclear cause for her cardiovascular symptoms, futher medication history was obtained. It was revealed that she was taking 100-150 tablets of loperamide per day. The decision was made to treat with intralipid emulsion therapy empirically given the strong suspicion for loperamide toxicity. The patient recovered well with supportive care. Loperamide levels returned elevated at 190 ng/mL. Repeated studies showed improvement of the conduction block, resolution of arrhythmias, and recovery of right and left ventricular function. Discussion: Acute loperamide toxicity can present as biventricular failure, with difficult-to-control arrhythmias. It requires a high index of suspicion. Treatment for loperamide toxicity is mainly supportive, lipid emulsion therapy can be considered in severe or refractory cases.

Early and aggressive presentation of wild-type transthyretin amyloid cardiomyopathy: A case report.

BACKGROUND: Wild-type transthyretin amyloidosis (ATTRwt) is the most common form of transthyretin amyloid cardiomyopathy, occurring mostly over age of 60 years (mean age of 80 years). Mean survival without treatment is 3.6 years, making early detection imperative. We report an unusual case of a 58-year-old patient with ATTRwt cardiomyopathy requiring heart transplantation. CASE SUMMARY: A 58-year-old male presented with progressive fatigue, shortness of breath, weight gain, leg swelling, orthopnoea, and paroxysmal nocturnal dyspnoea for several months. Approximately ten months before this clinical presentation, the patient had first received a diagnosis of heart failure with reduced ejection fraction (EF) of 15% to 20%. The patient was started on appropriate guideline-directed medical therapy with only mild improvement in his EF. Upon further investigation, echocardiogram, technetium pyrophosphate scan (Tc PYP), and cardiac magnetic resonance imaging (cMRI) suggested a diagnosis of amyloidosis, and ATTRwt was subsequently confirmed with native heart tissue biopsy, congo red staining, liquid chromatography-tandem mass spectrometry, and genetic testing. The patient was successfully treated with heart transplantation and is doing well post-transplant. CONCLUSION: Wild-type ATTR amyloidosis should be kept on differentials in all patients (even less than 60 years old) with non-ischemic cardiomyopathy, especially in the setting of increased ventricular wall thickness and other classic echocardiogram, cMRI, and Tc PYP findings. Early diagnosis and management can be consequential in improving patient outcomes.