Clinical validation of St. Thomas' Hospital cardioplegic solution No. 2 (Plegisol).

Recently, the St. Thomas' Hospital cardioplegic solution No. 2 (Plegisol) has become available commercially in the UK. In a series of patients (n = 28) undergoing open heart surgery for a variety of lesions, a clinical validation was performed. Preservation of myocardial contractility was assessed biophysically by quantitative birefringence measurements of myocardial biopsy samples (full thickness apical left ventricle and right ventricle) taken (1) prior to ischaemia, (2) at the end of ischaemia and (3) 10-15 min after reperfusion during cardiopulmonary bypass. In addition, serum CK-MB values were measured in samples taken throughout the operation and for 4 days postoperatively. Postoperative ECG traces (taken every 6 h for 48 h and then daily up to 7 days) were analysed to identify the occurrence of perioperative infarction. There were no hospital deaths. Chronotropic support was required in 5 of 28 patients (18%) for transient heart block. Low cardiac output did not occur postoperatively. Birefringence measurements in biopsy samples taken at the end of the ischaemic period (immediately prior to reperfusion) indicated an apparent left ventricular deterioration in myocardial contractility in 12 of 28 patients (43%) when compared to biopsies sampled prior to the ischaemic period. However, after 10-15 min of aerobic reperfusion, measurements indicated that myocardial contractility recovered to almost pre-ischaemic levels in the majority of patients. Thus, in 22 of 28 patients (79%), left ventricular deterioration did not occur in post-ischaemic biopsy samples when compared to the pre-ischaemic biopsies. Similarly, 21 of 28 patients (75%) had no deterioration of birefringence values in right ventricular biopsies.(ABSTRACT TRUNCATED AT 250 WORDS)