A midsystolic Doppler signal void was present in 142 of 606 patients (23.4%).
Doppler gradients may underestimate midapical obstruction when forward flow ceases during systole.
Signal void reflects dynamic apposition of hypertrophied midapical myocardial walls.
Signal void was associated with pronounced regional hypertrophy, smaller cavity size, lower absolute global longitudinal strain, elevated cardiac troponin I, and apical aneurysm.
The marker identified a distinct midapical HCM phenotype, but longitudinal clinical outcomes were not evaluated.
Guideline-Based Recommendations
This observational study did not issue clinical guidelines; the points below reflect its methods, findings, and clinical implications.
Diagnosis
The study defined HCM as maximal left ventricular wall thickness of at least 15 mm, or at least 13 mm with a family history or pathogenic genetic finding.
Signal void required continuous-wave Doppler aligned with the midapical left ventricular cavity, showing abrupt attenuation or near-complete absence of the velocity envelope during midsystole after initial systolic acceleration.
Management
Signal void may prompt targeted downstream imaging and inform management, but its diagnostic and prognostic value requires prospective validation.
Monitoring & Follow-up
Echocardiographic assessment may include left ventricular morphology, intracavitary flow, global longitudinal strain, and evaluation for apical aneurysm.
Prospective longitudinal studies are needed to determine whether early detection modifies clinical outcomes.
Risks
Signal void was associated with adverse structural features, including apical aneurysm and impaired longitudinal deformation.
The study did not establish that signal void independently predicts sudden cardiac death or arrhythmic events.
Patient & Prescribing Data
The study included 606 consecutive patients with HCM evaluated from November 2021 through December 2024.
Patients with significant valvular heart disease, prior septal reduction therapy, or known infiltrative or storage disorders were excluded. Comprehensive medication-exposure data were not available for all participants.
Clinical Best Practices
Perform comprehensive transthoracic echocardiography using standardized HCM imaging approaches.
Align continuous-wave Doppler with the midapical left ventricular cavity and confirm findings across multiple acoustic windows and cardiac cycles.
Exclude signal loss caused by Doppler misalignment or inappropriate gain settings.
Consider contrast echocardiography, cardiac CT, or cardiac magnetic resonance when standard transthoracic echocardiography is suboptimal or further anatomic clarification is required.
Related Resources & Content
American Society of Echocardiography recommendations for multimodality cardiovascular imaging in HCM
A practical approach to echocardiographic imaging in patients with hypertrophic cardiomyopathy
Doppler systolic signal void in hypertrophic cardiomyopathy: Apical aneurysm and severe obstruction without elevated intraventricular velocities
Obstruction in hypertrophic cardiomyopathy: Don’t forget midventricular obstruction
2020 AHA/ACC guideline for the diagnosis and treatment of hypertrophic cardiomyopathy
Moderate coffee consumption generally appeared safe for most adults, but randomized evidence suggested divergent effects on atrial fibrillation and premature ventricular contractions.
