Guidelines for Complications of Cancer Treatment Vol VIII Part B

Cardiac Morbidity & MortalityCardiovascular mortality contributes for approximately 10-15% of all causes of mortality. The various cardiaccomplications that have been observed after Hodgkin’s diseasetreatment includes pericarditis, pancarditis, pericardialeffusion, pericardial fibrosis, congestive heart failure, valvulardefects, conduction defects, and coronary artery disease. Themost common fatal cardiovascular complication has been acutemyocardial infarction secondary to coronary artery disease.Radiation related factors associated withCardiac Toxicity:Several types of damage were recognized, includingpericardial, myocardial and vascular. The risk of acute radiationpericarditis and delayed constrictive pericarditis afterirradiation for HD have been clearly associated with thevolume of heart irradiated and the dose of radiation received.Stewart and Fajardo and Stewart et al. estimated that thethreshold for significant pericardial injury is 40Gy if morethan 60% of the heart is included in the radiation field and15% if less than 15% of the cardiac volume is irradiated.Studies from the Stanford and University of California werethe first ones to indicate a dose-response relationship forradiation pericarditis and myocardial injury. Also frequencyof radiation related cardiac damage is related to the techniqueof irradiation employed. The original mantle field techniqueemployed equally weighted anterior and posterior fields, highdose-rate pulmonary irradiation, and no subcarinal block.Pericarditis was diagnosed in 17.1% (43/251) of patients whoreceived this treatment. The use of a “thin lung block” todecrease the dose rate to the lungs, and the addition of asubcarinal block to decrease the amount of pericardium treatedto the full dose decreased the frequency of pericarditis to 2.5%.The frequency of pericarditis was 3.2% in a series of adult302