Related Experiment Videos
[Changes in left ventricular filling in obstructive cardiomyopathies during long term beta blockade]
Insights
Beta blockade significantly improves left ventricular filling in hypertrophic cardiomyopathy patients, leading to symptomatic relief. Non-responders show persistent filling abnormalities due to irreversible cardiac morphology changes.
Area of Science:
- Cardiology
- Pharmacology
Context:
- Hypertrophic cardiomyopathy (HCM) is a complex cardiac condition.
- Left ventricular (LV) filling abnormalities are common in HCM, impacting symptoms.
Purpose:
- To investigate the mechanism of symptomatic improvement in patients with obstructive hypertrophic cardiomyopathy during long-term oral beta-blockade therapy.
- To identify predictors of response to beta-blockade in HCM.
Summary:
- This study examined LV filling using echocardiography and cineangiography in 37 obstructive HCM patients before and during propranolol treatment.
- Clinical improvement correlated strongly with enhanced LV filling parameters, including maximum filling velocity and duration.
- Two patient groups emerged: 'reactors' with improved filling and asymptomatic status, and 'non-reactors' with poor filling due to irreversible morphological changes.
Impact:
- Beta-blockade therapy can significantly improve LV filling dynamics in HCM patients.
- Identifying 'reactors' and 'non-reactors' aids in understanding treatment response and prognosis in HCM.
- Findings highlight the role of LV filling and morphology in HCM management and therapeutic outcomes.
Abstract:
Left ventricular filling was studied by echocardiography and cineangiography in 37 patients with hypertrophic cardiomyopathy with obstruction before and during long-term oral beta blockade (166 +/- 61 mg propranolol for 15.6 +/- 21 months on average) in order to determine the mechanism of symptomatic improvement in these patients. This study confirmed that clinical improvement is related to a great degree to the improvement in the parameters of left ventricular filling. In addition, two groups of patients may be identified: the "reactors", that is to say the patients who remained or became asymptomatic, characterised by a significant improvement in the indices of left ventricular filling (maximum filling velocity p < 0.01, duration of rapid filling p < 0.05, left ventricular compliance--volumic kGaasch p < 0.001, parietal ks Mirsky p < 0.01). The "non-reactors" were characterised by very poor indices of left ventricular filling. These abnormalities are principally related to severe and irreversible changes in left ventricular and mitral valve morphology.