Interventricular conduction disorders after orthotopic heart transplantation: risk factors and clinical relevance.

BACKGROUND

Causes and significance of interventricular conduction disorders (IVCDs) after orthotopic heart transplantation (OHT) are still unknown.

METHODS

We retrospectively researched the presence of IVCDs in 240 patients who underwent bicaval OHT in three time periods: at day 1, after 1 year, and after 3 years from OHT. To evaluate the impact of the surgical technique, a control population treated with biatrial anastomosis was used.

RESULTS

The most common IVCD was right bundle branch block (RBBB). Its presence at day 1 correlated with transpulmonary gradient before OHT. Its presence after 1 year and its development correlated with a 1-month acute rejection score≥2 (p = .050 and p = .006). The incidence of RBBB was higher in the biatrial control population (40.7% vs 23.8%, p < .001).

CONCLUSIONS

RBBB is the most common IVCD. Its presence can be explained by a susceptibility of the right branch to heart positioning, pressure overload, and acute rejection. IVCDs do not affect prognosis.