Cardiovascular manifestations are a frequent finding in hyperthyroid and hypothyroid states. In this review, potential mechanisms by which thyroid hormones may exert their cardiovascular effects and pathophysiological consequences of such effects are briefly discussed. Two major concepts have emerged about how thyroid hormones exert their cardiovascular effects. First, there is increasing evidence that thyroid hormones exert direct effects on the myocardium, which are mediated by stimulation of specific nuclear receptors, which in turn leads to specific mRNAs production. Furthermore, there is some evidence that thyroid hormones may also activate extranuclear sites and may directly alter plasma membrane function. Second, thyroid hormones interact with the sympathetic nervous system by altering responsiveness to sympathetic stimulation presumably by modulating adrenergic receptor function and/or density. Pathophysiological consequences of such direct and indirect thyroid hormone effects include increased myocardial contractility and relaxation that may be related to stimulation by T3 of specific myocardial enzymes. However, when left ventricular hypertrophy occurs in association with hyperthyroidism, it may be related to either direct thyroid hormone-induced stimulation of myocardial protein synthesis or to thyrotoxicosis-induced increases in cardiac work load. Although hyperthyroidism generally has little or no effect on mean arterial blood pressure, hypothyroidism is often associated with increases in diastolic blood pressure that are reversible after hormone substitution and may be mediated in part by sympathetic activation. Moreover, there is increasing evidence that thyroid hormones have direct chronotropic effect on the heart that are independent of the sympathetic nervous system.(ABSTRACT TRUNCATED AT 250 WORDS)

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BACKGROUND Long-term trends of the incidence and outcome of cardiogenic shock (CS) patients are scarce. We analyze for the first time trends in the incidence and outcome of CS during a 20-year period in Switzerland. METHODS AND RESULTS The AMIS (Acute Myocardial Infarction in Switzerland) Plus Registry enrolls patients with acute myocardial infarction from 83 hospitals in Switzerland. We analyzed trends in the incidence, treatment, and in-hospital mortality of patients with CS enrolled between 1997 and 2017. The impact of revascularization strategy on outcome was assessed for the time period 2005 to 2017. Among 52 808 patients enrolled, 963 patients were excluded because of missing data and 51 842 (98%) patients remained for the purpose of the present analysis. Overall, 4090 patients (7.9%) with a mean age of 69.6±12.5 years experienced acute myocardial infarction complicated by CS. Overall, rates of CS declined from 8.

Some studies have reported increased short-term mortality and higher incidence of multivessel coronary artery disease in patients with inferior myocardial infarction and complete heart block, but information is lacking on clinical outcome after hospital discharge. Therefore, data were obtained and analyzed in 749 patients who were admitted with inferior myocardial infarction to four different centers and followed up for 1 year. Six hundred fifty-four patients (Group 1) did not have complete heart block and 95 (Group 2) had complete heart block during their hospital stay (incidence rate 12.8%). Compared with Group 1, Group 2 patients were older (66 versus 61 years, p less than 0.01), more often had signs of left ventricular failure (p less than 0.001) and had higher peak creatine kinase values (1,840 versus 1,322 IU/liter, p less than 0.001). The in-hospital mortality rate was higher in Group 2 than in Group 1 (24.2 versus 6.3%, p less than 0.001). However, at discharge there was no difference between Group 1 and Group 2 in clinical characteristics, left ventricular ejection fraction (0.52 +/- 0.12 versus 0.52 +/- 0.11) or incidence of complex ventricular arrhythmias on ambulatory electrocardiographic monitoring. Furthermore, during the year after hospital discharge, patients in Groups 1 and 2 did not have significantly different mortality rates (6.4 versus 10.1%, p = NS). The incidence rate of reinfarction (4%) was the same in Groups 1 and 2. The incidence of coronary artery bypass surgery was slightly but not significantly higher in Group 1 compared with Group 2 (11 versus 4%).(ABSTRACT TRUNCATED AT 250 WORDS)