Objective: To study the specific cardiac abnormalities associated with pheochromocytoma and to suggest a strategy for evaluating cardiac function in patients with pheochromocytoma.
Methods: In this case-control study, we reviewed pathology records of patients seen at Cedars-Sinai Medical Center between 1997 and 2007; patients with adrenal or extra-adrenal pheochromocytoma and those with nonfunctioning benign or malignant adrenal tumors were identified. Patients with functioning adrenal adenomas that secreted cortisol or aldosterone were excluded. Clinical history, imaging, pathology, biochemical test results, electrocardiographic findings, and echocardiographic findings were compared between patients with pheochromocytoma and patients with nonfunctioning adrenal tumors.
Results: The charts of 22 patients with pheochromocytoma and 35 patients with nonfunctioning adrenal tumors were included. No perioperative mortality was observed. The average age of patients with pheochromocytoma was similar to that of control patients (51.9 +/- 3.9 years vs 60.2 +/- 2.5 years, respectively), as was the number of patients with known cardiovascular diseases (2 [9%] in the pheochromocytoma group vs 5 [14%] in the control group). Two patients with pheochromocytoma (9%) exhibited myocardial damage. Abnormal electrocardiographic findings were present in 16 patients with pheochromocytoma (73%) and in 17 control patients (49%) (P = .1). QTc was prolonged in patients with pheochromocytoma compared with control patients (448.3 +/- 9.7 ms vs 424.7 +/- 4.5 ms, respectively; P = .02) and was correlated with levels of norepinephrine and normetanephrine, but not with levels of epinephrine and metanephrine or tumor size. ST-T abnormalities were present in 11 patients with pheochromocytoma (50%) and in 8 control patients (23%) (P = .04). Echocardiographic findings were normal in most patients with pheochromocytoma; abnormal left ventricular wall motion was documented in 3 patients with long QTc.
Conclusions: The specific electrocardiographic findings in patients with pheochromocytoma are prolonged QTc and ST-T abnormalities. Performing an electrocardiogram in patients with pheochromocytoma would be prudent. Echocardiography would be useful to examine LV wall motion in patients with long QTc. Coronary artery disease should be excluded in patients with significant ST-T changes.