Cardiac and Vascular Changes in Pheochromocytoma and Paraganglioma

Overview

PHEOCHROMOCYTOMA (PCC)/ PARAGANGLIOMA are catecholamine secreting tumors with varied manifestations. Besides hypertension, PCC patients may have subclinical to overt cardiac and vascular dysfunction, which are important to recognize to minimize perioperative morbidity and mortality. Cardiovascular (CV) dysfunction can be in the form of hypertension, left ventricular (LV) hypertrophy, heart failure, cardiomyopathy, dysrhythmias, angina and Myocardial infarction. Literature search revealed a few retrospective and a few prospective studies, including one prospective follow up study conducted at SGPGIMS to document CV changes in PCC. Our institutional study was the first to document the nature and extent of CV dysfunction and cardiomyopathy and their reversal after surgical cure. The studies revealed that PCC patients had significantly higher LV mass index, higher LV diastolic dysfunction, subclinical impaired LV systolic function. Earlier studies postulated apparent improvement in various cardiac indices even with selective α-blockade and continued after surgical cure, with near normalization at 3 -6 months postoperatively. Detailed cardiac and vascular evaluation in PCC patients can be of help in preoperative optimization of cardiac risk and may provide prognostic information The literature on PCC-mediated CV dysfunction and catecholamine cardiomyopathy is largely limited to case reports and retrospective studies, with few reports of their reversal after curative PCC operations. Whether the duration of disease influence the function of heart was not apparently addressed in earlier trials. Trials that established the differences in the degree of cardiac dysfunction between normotensive and hypertensive PCC patients involved smaller proportion of study subjects. Sub clinical changes in endomyocardium was presumed but not objectively assessed and hence its reversal after surgical cure is uncertain. The aim of this research is to study the cardiac and vascular changes in Pheochromocytoma/ Paraganglioma patients and their reversal following curative surgery

The aim of this research is to study the cardiac and vascular changes in Pheochromocytoma/ Paraganglioma patients and their reversal following curative surgery This prospective, case-control study is conducted at SGPGIMS, Lucknow, India, tertiary care referral institute, between January 2019 and September 2021 after approval from institutional ethics committee. The study group includes 50 biochemically and histopathology proven PCC /Paraganglioma patients, who after 1 to 3 weeks of α-adrenoceptor blockade with oral prazosin undergo primary laparoscopic or open surgery. Cure of hypercatecholaminism will be documented by normal 24-hour urinary fractionated metanephrine values at 7-10 days postoperatively. Two contemporary age- and gender-matched control groups includes 10 newly detected (withtin 3 months) Essential Hypertensive (E-HT) patients, who will undergo treatment with standard anti- HT medications and 10 Healthy individuals (normal in physical examination, ECG , Echo), that include hospital staff nurses, technicians, doctors whom would be requested to volunteer. METHODOLOGY Patients in the study group, besides the usual evaluation of PCC, also undergo detailed cardiac and vascular evaluation, at diagnosis, at 7- 10 days of α-blockade, and 7 days, 3 and 6 months post adrenalectomy/ Paraganglioma excision and in control groups - E-HT controls, cardiac evaluation is done at diagnosis and after 3 months of anti HT medications ; in Healthy individuals, cardiac evaluation is done at the start of study and after 6 months. The CV evaluation includes 2D-echocardiography, speckle tracking Echo (for measuring global longitudinal strain), serum NT-proBNP estimation and flow mediated vasodilatory studies by Doppler Ultrasonography of the brachial artery to assess the endothelial dependent and smooth muscle dependent vasodilatory responses