Heart failure & cardiomyopathiesCohort study
Electromechanical profiling in genotyped dilated cardiomyopathy with left bundle branch block
- Multicentre cohort study
- consecutive patients
Authors' conclusion
Genetic testing has a low diagnostic yield in patients with DCM and LBBB. Genotype-positive variants exhibit a distinct electromechanical profile, characterised by atypical electrocardiographic features and markedly reduced mechanical dyssynchrony, poor CRT response, and worse long-term outcomes.
Study context
- Population
- Dilated cardiomyopathy (DCM) patients with left bundle branch block (LBBB) undergoing genetic testing (20 ClinGen genes) and electro- and echocardiographic phenotypingfrom cohort of 1206 DCM
- Participants
- 347 patients
- Exposure
- Genotype-positive vs genotype-negative
- Genotype-positiven = 22
- Outcome
- Composite of:
- All-cause mortality
- Heart transplantation/LV assist device implantation
- HF hospitalization
Main finding
As reported in the abstract
Worse clinical outcomes in genotype-positive (both composite outcome and heart failure hospitalization (HFH))
P<0.001
Observational data: associations, not effects.
Further findings
| Outcome | P value |
|---|---|
| Reverse remodelling after CRT (ΔLVEF) · ΔLVEF 1%[−6-6] vs. 14%[7-22] | P < 0.001 |
Diagnostic yield of genetic testing (P/LP variants)
- Patients with P/LP variants among 347 DCM patients with LBBB
- 22 (6%)
Strict LBBB criteria (Strauss) and mechanical dyssynchrony
- Genotype-positive less often fulfilled strict LBBB criteria (Strauss)
- P < 0.001
- Genotype-positive showed less mechanical dyssynchrony (predominantly LBBB-0/1)
- P < 0.001
- Advanced LBBB stages excluded an underlying rare genetic variant
Predictors of cardiac resynchronization therapy (CRT) response and composite outcome
- P/LP variant status, left ventricular ejection fraction (LVEF) and LBBB stage independently predicted CRT response and composite outcome
Original publication
Summarised from the published abstract; every number is checked against it