Cardiac resynchronisation therapy among adults with a systemic right ventricle: a multicentre experience.

BACKGROUND

Cardiac resynchronisation therapy (CRT) is a key treatment for heart failure (HF) in acquired heart disease, but its benefits in adults with congenital heart disease and a systemic right ventricle (sRV) remain unclear. This study aimed to assess whether CRT improves outcomes in patients with sRV.

METHODS

This is an international, retrospective study including patients >18 years from 33 centres with transposition of the great arteries (TGA) following atrial switch operation and congenitally corrected TGA. The primary endpoint included overall survival and survival free from HF. The secondary endpoint was a composite of death, hospitalisation for HF, heart transplant, mechanical support and ventricular tachycardia/implantable cardioverter-defibrillator therapies.

RESULTS

We identified 105 out of 1721 patients (3.5%) who underwent CRT. Median follow-up after CRT implant was 4.6 (1.6-8) years. QRS improvement was limited to those with previous pacing (167±35 vs 154±28 ms; p=0.002). Following CRT, there was no significant change in B-type natriuretic peptide values, peak VO2 and tricuspid regurgitation severity by echocardiography. CRT complications occurred in 10 (9.5%), though they were usually minor. Patients with CRT were propensity-matched to controls according to age, sex, anatomy, presence of complex disease, previous HF and sRV dysfunction at baseline. At univariable analysis, CRT (HR 4.39-95%, CI 1.6 to 11.9; p=0.003), older age and moderate-to-severe sRV dysfunction at baseline were predictive of death, while CRT (HR 3-95%, CI 1.3 to 7; p=0.01) and sRV dysfunction were associated with HF admission. By multivariable analysis, CRT (HR 8.8-95%, CI 2.9 to 26.6; p=0.0001) and age (HR 1.1%-95%, CI 1.01 to 1.15; p<0.0001) were independently associated with poorer outcome.

CONCLUSION

In this retrospective study in the largest population thus far described with an sRV, CRT implant was not associated with improved survival, even after controlling for key confounders.