It can cause cardiac hypertrophy... but you probably don't need to worry about it if low dosages are used...
..."THE EFFECTS OF GH on the cardiovascular system have been well documented in disorders with excessive or deficient GH production. GH excess in humans is accompanied by myocardial hypertrophy, which initially enhances cardiac output (1) but ultimately leads to diminished cardiac performance (2). Conversely, GH deficiency leads to reduced cardiac muscle mass (3) and consequently to impaired cardiac function..."
Blood pressure-independent cardiac hypertrophy in acromegalic patients.
Ciulla M, Arosio M, Barelli MV, Paliotti R, Porretti S, Valentini P, Tortora G, Buonamici V, Moraschi A, Capiello V, Magrini F.
Istituto di Clinica Medica Generale e Terapia Medica, Centro di Fisiologia Clinica e Ipertensione, Universita di Milano, Italy. email@example.com
OBJECTIVE: Acromegaly is frequently associated with an increase in left ventricular mass, even in the absence of systemic hypertension. Pathological studies on acromegalic hearts have shown an extensive interstitial fibrosis, suggesting the existence of a specific acromegalic cardiomyopathy. The aim of this study was to assess left ventricular wall structure in acromegaly by ultrasonic tissue characterization. DESIGN AND METHODS: We studied 10 untreated acromegalic patients and 10 age-matched healthy control subjects. The echo patterns of two-dimensional long-axis end-diastolic echocardiograms were assessed by colour-scale analysis of the interventricular septum, with estimates of the mean colour scale value, the broad band (Bb) and the derived collagen volume fraction (dCVF). We also measured electrocardiographic QT interval dispersion (QTd) as a marker of dyshomogeneous ventricular repolarization. RESULTS: Seven patients had left ventricular hypertrophy according to the sex-independent criteria; of these, two had arterial hypertension. None of our patients had echocardiographic evidence of diastolic or systolic dysfunction. All patients showed significantly increased myocardial echoreflectivity (Bb = 106.4+/-12.1 versus 79.3+/-6.5; dCVF% = 2.78+/-0.53 versus 1.58+/-0.29; P < 0.0001) and QTd (66+/-13 ms versus 54+/-8 ms, P < 0.05). A significant correlation was found between dCVF and the duration of acromegaly (r = 0.80; P = 0.005). CONCLUSIONS: Left ventricular remodelling observed in acromegaly is not related to the presence of arterial hypertension; we hypothesize that the increased echoreflectivity and QTd are long-term consequences of cardiac hypertrophy and prolonged exposure to high levels of growth hormone and insulin-like growth factor-I.
Impaired cardiac performance is a distinct feature of uncomplicated acromegaly
S Fazio, A Cittadini, A Cuocolo, B Merola, D Sabatini, A Colao, B Biondi, G Lombardi and L Sacca
Department of Internal Medicine, Federico II University Medical School, Naples, Italy.
This study was designed to assess right and left ventricular function in patients with active acromegaly. To this end, 26 acromegalic patients (9 of whom had arterial hypertension) and 15 normal subjects of comparable age and sex distribution were studied by radionuclide angiography at rest and during supine bicycle-ergometer exercise and echocardiography. At rest, the filling rates of left (-19%; P < 0.005) and right ventricle (-32%; P < 0.001) were significantly reduced in acromegalic patients, whereas right and left ventricle ejection fractions (EFs) were normal. During physical exercise, EF was considerably lower in the acromegalic patients than in controls. This was true for both left (61 +/- 11% vs. 75 +/- 8%; P < 0.001) and right ventricle (45 +/- 13 vs. 58 +/- 11%; P < 0.002). In as many as 73% of patients, EF increased less than 5%, thus fulfilling the criteria for impaired cardiac performance. Left ventricular mass index was 60% greater in acromegalics than in controls (P < 0.001). A significant difference in left ventricular mass index was also present when normotensive acromegalic patients were compared with controls (P < 0.001). No significant difference in the indices of systolic and diastolic function was observed between the subgroups of normotensive and hypertensive acromegalics, either at rest or during exercise. The data demonstrate that in uncomplicated acromegaly, besides cardiac hypertrophy, there are also important alterations of systolic and diastolic function of both ventricles, leading to a significant impairment of cardiac performance.
Role of growth hormone in chronic heart failure: therapeutic implications.
Volterrani M, Giustina A, Manelli F, Cicoira MA, Lorusso R, Giordano A.
Division of Cardiology, Salvatore Maugeri Foundation, Medical Center, Gussago, Italy. firstname.lastname@example.org
Chronic heart failure is a multi-etiological cardiovascular disorder with high prevalence and poor prognosis. Medical treatment of dilated cardiomyopathy is aimed at alleviating heart failure symptoms. Diuretics, angiotensin-converting enzyme (ACE) inhibitors and very recently, beta-blockers have been shown to have favorable effects on symptoms, exercise capacity and mortality. Growth hormone (GH) and insulin-like growth factor (IGF)-1 are involved in several physiological processes such as the control of muscle mass and function, body composition and regulation of nutrient metabolism. The role of GH and IGF-1 as modulators of myocardial structure and function is well established. Receptors for both GH and IGF-1 are expressed by cardiac myocytes; therefore, GH may act directly on the heart or via the induction of local or systemic IGF-1, while IGF-1 may act by endocrine, paracrine or autocrine mechanisms. Patients with acromegaly have an increased propensity to develop ventricular hypertrophy and cardiovascular diseases; impaired cardiac efficiency can also be observed in patients with GH deficiency....