[An electrocardiographic study of cardiac damage following post-operative radiation in patients with mammary carcinoma on the left (author's transl)].

Systematic ECG-analysis were performed in 13 patients (mean age 55.1 years) with mammary carcinoma on the left, prior to, during, and 4 months after postoperative radiation therapy. Treatment was done with a gammatron, the average load to the anterior cardiac wall amounted to 36 Gy. All patients exhibited ST-T segment changes, flat, isoelectric or coronary negative T-waves in the precordial leads demonstrating radiation-induced perimyocarditis. Prolongation of QT-interval corrected with Bazett's formula (QTc) was observed in 6 patients showing myocardial damage. Sinus tachycardia in 9 patients and lower voltage in 3 patients gave a hint to early appearance of pericardial effusions. Pulmonary P-waves in 6 patients and shift of QRS-axis to the right in 5 patients demonstrated early damage of the right heart. Clinical deterioration could not be seen in any patient.