Project description:BackgroundWe report endocardial radiofrequency (RF) ablation as an alternative treatment approach for a symptomatic patient with obstructive hypertrophic cardiomyopathy (oHCM), who is not suitable for surgical septal myectomy or alcohol septal ablation. Endocardial RF ablation, with detailed 3D mapping of the intrinsic conducting system, offers the possibility of reducing the risk of complete heart block rates and of effectively relieving symptoms.Case summaryWe present a symptomatic 51-year-old female patient with oHCM and a maximum left ventricular outflow tract (LVOT) gradient of 148 mmHg. Because of alcohol septal ablation failure, endocardial RF ablation in combination with detailed mapping of the intrinsic conduction system and intraprocedural imaging was performed. The 6-month follow-up showed a significant improvement in exercise tolerance, no relevant dynamic LVOT obstruction with a gradient of 22 mmHg under Valsalva.DiscussionIn the current case report, endocardial RF ablation persistently reduced LVOT gradients in a patient with oHCM. Pre-interventional imaging, detailed 3D mapping of the conduction system, and correlation to intracardiac and transthoracic echocardiography were key for an effective and safe ablation of a small target zone.
Project description:To understand the interplay between cardiomyocyte and nonmyocyte cell types in human obstructive and non-obstructive hypertrophic cardiomyopathy, single nuclei RNA-sequencing was performed on 2 unused donor hearts, 1 obstructive HCM specimen, and 6 non-obstructive HCM specimens.
Project description:A diastolic murmur is informative in the diagnosis of valvular heart disease, such as mitral stenosis and aortic regurgitation. Patients with hypertrophic cardiomyopathy (HCM) could have diastolic murmurs, although this is not widely recognized. We describe an illustrative case of HCM which was found to have a diastolic murmur associated with mid-left ventricular obstruction. An asymptomatic 65-year-old male was referred because of an abnormal electrocardiogram. Cardiac auscultation showed a soft fourth heart sound, a systolic ejection murmur, and a third heart sound followed by a diastolic murmur at the apex. On phonocardiography, the mid-diastolic murmur was predominantly low-pitched with an onset of about 200 ms after the second heart sound and a duration of approximately 150 ms. The timing of the diastolic murmur was consistent with an increased blood inflow during diastole in the mid-ventricular obstruction (2.0 m/s), which was produced by narrowing between the hypertrophied ventricular septum and the protrusion of the anterior papillary muscle. <Learning objective: A diastolic murmur is common in valvular heart diseases, such as mitral stenosis and aortic regurgitation, and can also be heard in hypertrophic cardiomyopathy although not widely recognized. We report an illustrative case of hypertrophic cardiomyopathy with a diastolic murmur related to mid-left ventricular obstruction, findings that would highlight the importance of auscultation regarding not only the differential diagnosis but also risk stratification, given the possible association of diastolic murmurs with adverse outcomes, even in the era of advanced imaging techniques.>.
Project description:Obstructive hypertrophic cardiomyopathy results from asymmetric septal hypertrophy, which eventually obstructs the outflow of the left ventricle. Obstructive hypertrophic cardiomyopathy is linked to mutations in genes that encode for sarcomere proteins, including actin, β-myosin heavy chain, titin, and troponin. The mutations lead to structural abnormalities in myocytes and myofibrils, causing conduction irregularities and abnormal force generation. Obstructive hypertrophic cardiomyopathy is a chronic disease that worsens over time, and patients become at higher risk of developing atrial fibrillation, heart failure, and stroke. Up until recently, there were no disease- specific medications for obstructive hypertrophic cardiomyopathy. Nevertheless, the US Food and Drug Administration approved mavacamten on April 28, 2022, for the treatment of symptomatic obstructive hypertrophic cardiomyopathy (New York Heart Association class II to III) in adults to improve functional capacity and symptoms. Its approval was based on data from EXPLORER- HCM and EXPLORER-LTE (NCT03723655). Mavacamten is a novel, first-in-class, orally active, allosteric inhibitor of cardiac myosin ATPase, which decreases the formation of actin- myosin cross-bridges, and thus, it reduces myocardial contractility, and it improves myocardial energetics. It represents a paradigm-shifting pharmacological treatment of obstructive hypertrophic cardiomyopathy. In this review, we describe its chemical and mechanistic aspects as well as its pharmacokinetics, adverse effects and warnings, potential drug-drug interactions, and contraindications.
Project description:BackgroundHypertrophic cardiomyopathy (HCM) is an inherited condition characterized by left ventricular (LV) hypertrophy unexplained by increased afterload, often with concomitant outflow tract obstruction. Verapamil is commonly used to treat symptomatic patients. However, its potential for adverse effects should be recognized.Case summaryThis report provides a case of cardiogenic shock in HCM, where a patient presented with chief complaint of fatigue and shortness of breath with an acute decline in LV systolic function on echocardiogram. His symptoms were attributed to verapamil toxicity following a recent increase in dosage. He achieved rapid symptom relief after holding his home medications, in addition to conservative management.DiscussionThis case report aims to elucidate the potential for multiple adverse effects involved with verapamil use in patients with obstructive HCM.
Project description:This case report concerns an 81-year-old woman with previously well-controlled hypertrophic obstructive cardiomyopathy (HOCM). She was referred to our hospital because of the acute onset of takotsubo syndrome. Echocardiography revealed basal hyperkinesis due to takotsubo syndrome superimposed on septal hypertrophy, which resulted in the reappearance of prominent left ventricular outflow tract obstruction (LVOTO). Although she developed cardiogenic shock triggered by atrial fibrillation, LVOTO was successfully mitigated by aggressive fluid resuscitation, rhythm control, and the administration of β-blocker. We herein report a rare case with catastrophic hemodynamics due to the incidental combination of HOCM and takotsubo syndrome.