Adenosine as an adjunct to inducing rapid asystole during cardioplegic arrest

A study was undertaken in 68 patients to assess the beneficial effect of adenosine as an adjunct to K(+)-enriched cardioplegia to induce rapid asystole. In the study group (n = 22), adenosine was given in the dose of 3 mg bolus into the aortic root immediately after aortic cross clamp along with K(+)-enriched cardioplegia. In the control group (n = 46) K(+)-enriched cardioplegia solution was used without adenosine. Important parameters monitored were: time to asystole in seconds and recovery of normal sinus rhythm following release of aortic cross clamp. In addition, standard haemodynamic parameters were measured. The results showed a marked reduction in the time to achieve asystole in the study group (3.53 +/- 1.18 seconds) as compared to the control group (18.19 +/- 11.80 seconds) (p < 0.001). Restoration of sinus rhythm was achieved in the study group at 43.53 +/- 33.60 seconds while in the control group it was achieved at 161.90 +/- 11.36 seconds (p < 0.001). The haemodynamic parameters measured 10 minutes after the termination of cardiopulmonary bypass were not different in the two groups. When measured one hour after the termination of cardiopulmonary bypass, haemodynamic parameters in the study group revealed a statistically significant improvement in inotropicity. No side effects or complications were encountered in the study group. We conclude that adenosine given as an adjunct to K(+)-enriched cardioplegia helps to achieve rapid asystole and faster recovery of sinus rhythm with no adverse effects and may aid in better myocardial preservation.