Acute myocardial infarction and underlying stenosis severity.

OBJECTIVES: The objective of this study was to investigate the underlying stenosis severity of the culprit lesion in acute myocardial infarction. BACKGROUND: It is widely believed that myocardial infarction often occurs in angiographically mild luminal stenosis. This, however, is in contradiction with experience from interventional practice in primary PCI. METHODS: We performed quantitative coronary angiography (QCA) in 250 consecutive patients referred for acute percutaneous coronary intervention (PCI) because of acute myocardial infarction (AMI). Fundamental for analysis was that a realistic estimate of underlying luminal narrowing before the infarction could be made angiographically that QCA could be performed and that one of two criteria was met: (1) spontaneous reflow allowing assessment of the lumen proximal and distal to the culprit lesion, or (2) coronary artery closed at arrival but reflow after uncomplicated wiring allowing assessment of the lumen proximal and distal to the culprit lesion. RESULTS: Of 250 consecutive patients (mean age 61.7 +/- 12.7 years, 48 women) referred for acute PCI, 156 patients (62%) fulfilled at least one of the above criteria for reliable QCA. In 151 of these patients (96%) the severity of the underlying stenosis was >50% and in 103 (66%) it was >70%. There were no differences in stenosis severity between the left anterior descending [LAD, (72 +/- 13)%, n = 57], left circumflex [Cx, (74 +/- 10)%, n = 20], and right coronary artery territory [RCA, (74 +/- 12)%, n = 76] (ANOVA, P = 0.76). There were no differences in stenosis severity between women [(73 +/- 13)%, n = 36] and men [(75 +/- 11)%, n = 120; P = 0.35]. CONCLUSION: In contrast to what is often believed, the majority of myocardial infarctions occurs in significant stenosis.     

Subclinical hypothyroidism is associated with coronary artery disease in older persons

BACKGROUND: We report the prevalence of coronary artery disease (CAD) associated with subclinical hypothyroidism in older persons. METHODS: We investigated the prevalence of subclinical hypothyroidism and its association with dyslipidemia and with CAD in 170 women and 110 men, mean age 75 +/- 9 years, in an academic nursing home. RESULTS: Of 280 persons, 18 (6%) had subclinical hypothyroidism, 18 (6%) had treated clinical hypothyroidism, 13 (5%) had subclinical hyperthyroidism, and 231 (83%) were euthyroid. Dyslipidemia occurred in 15 of 18 persons (83%) with subclinical hypothyroidism, in nine of 18 persons (50%) treated for hypothyroidism, in six of 13 persons (46%) with subclinical hyperthyroidism, and in 128 of 231 euthyroid persons (55%) (p <.025 comparing subclinical hypothyroidism with euthyroidism and p <.005 comparing subclinical hypothyroidism with treated hypothyroidism and with subclinical hyperthyroidism). CAD was present in 10 of 18 persons (56%) with subclinical hypothyroidism, in nine of 18 persons (50%) with treated hypothyroidism, in 5 of 13 persons (38%) with subclinical hyperthyroidism, and in 38 of 231 euthyroid persons (16%) (p <.001 comparing subclinical hypothyroidism with euthyroidism; p <.005 comparing treated hypothyroidism with euthyroidism; and p <.05 comparing subclinical hyperthyroidism with euthyroidism). CONCLUSIONS: Subclinical hypothyroidism was associated with a high prevalence of dyslipidemia and a high prevalence of CAD.     

The effects of off-normal hours, age, and gender for coronary angioplasty on hospital mortality in patients undergoing coronary angioplasty for acute myocardial infarction

Percutaneous transluminal coronary angioplasty (PTCA) was performed in all 1,050 patients hospitalized within 24 hours of symptoms of documented acute myocardial infarction (AMI) from 1998 to 2002. Hospital mortality was similar in women and men who underwent PTCA for AMI but was higher in patients aged 75 to 95 years (10%) than in patients aged 21 to 50 (2.1%, p <0.001), 51 to 64 (2.3%, p <0.001), and 65 to 74 years (4%, p <0.02). Hospital mortality was higher in patients who had PTCA for AMI during off-normal (5.8%) than normal hours (3.2%, p <0.05).     

The meaning of hypokalemia in heart failure

Maintenance of normal potassium (K(+)) homeostasis has become an increasingly important limiting factor in the therapy of heart failure (HF). With the application of loop diuretics and digoxin, hypokalemia has become a frequent and feared side effect of treatment. Low serum K(+) in HF may be also a marker of increased neurohormonal activity and disease progression. To gain the maximum benefit from treatment, we need to individualize drug use and carefully monitor electrolytes. Symptomatic HF patients (New York Heart Association class III-IV) should be prescribed the lowest dose of diuretic necessary to maintain euvolemia. Mild hypokalemia may be corrected by the use of aldosterone receptor antagonists such as spironolactone or eplerenone. However, a more severe hypokalemia should preferably be corrected using K(+) supplement. Serum K levels should be frequently checked and maintained between 4.0 and 5.5 mEq/l (mmol/l).     

Cardiovascular drugs in pregnancy

Cardiovascular drugs are used in pregnancy to treat maternal and fetal conditions. Mothers may also require drug therapy postpartum. Most cardiovascular drugs taken by pregnant women can cross the placenta and therefore expose the developing embryo and fetus to their pharmacologic and teratogenic effects. These effects are influenced by the intrinsic pharmacokinetic properties of a given drug and by the complex physiologic changes occurring during pregnancy. Many drugs are also transferred into human milk with potential adverse effects on the nursing infant. This article summarizes some of the literature concerning the risks and benefits of using cardiovascular drugs during pregnancy.