Differences between diabetic and non-diabetic hypertensive patients with first acute non-ST elevation myocardial infarction and predictors of in-hospital complications

Hypertension and acute myocardial infarction: an overview

History of hypertension is a frequent finding in patients with acute myocardial infarction (AMI) and its recurring association with female sex, diabetes, older age, less frequent smoking and more frequent vascular comorbidities composes a risk profile quite distinctive from the normotensive ischemic counterpart.Antecedent hypertension associates with higher rates of death and morbid events both during the early and long-term course of AMI, particularly if complicated by left ventricular dysfunction and/or congestive heart failure. Renin-angiotensin-aldosterone system blockade, through either angiotensin-converting enzyme inhibition, angiotensin II receptor blockade or aldosterone antagonism, exerts particular benefits in that high-risk hypertensive subgroup.In contrast to the negative implications carried by antecedent hypertension, higher systolic pressure at the onset of chest pain associates with lower mortality within 1 year from coronary occlusion, whereas increased blood pressure recorded after hemodynamic stabilization from the acute ischemic event bears inconsistent relationships with recurring coronary events in the long-term follow-up.Whether antihypertensive treatment in post-AMI hypertensive patients prevents ischemic relapses is uncertain. As a matter of fact, excessive diastolic pressure drops may jeopardize coronary perfusion and predispose to new acute coronary events, although the precise cause-effect mechanisms underlying this phenomenon need further evaluation.

Simultaneous renal hypertension and type 2 diabetes exacerbate vascular endothelial dysfunction in rats

Despite the high rate of occurrence of both diabetes and hypertension in humans, the cardiovascular effects of the two conditions have not been investigated when they occur simultaneously. Thus this study examined the vascular effects of simultaneous type 2 diabetes and renal hypertension on endothelial function. Serum malondialdehyde and systolic blood pressure (SBP) were measured, glucose tolerance test (GTT) was performed, and concentration-response to phenylephrine (PE) in the absence and presence of nitro-l-arginine methyl ester (l-NAME), acetylcholine and sodium nitroprusside were conducted on aortic rings from diabetic control, type 2 diabetes, sham-operated, renal hypertensive, and simultaneous type 2 diabetes plus hypertension rats respectively. Hypertension, diabetes, and simultaneous diabetes and hypertension were associated with either increased or decreased maximal responses (E(max)) of PE dependent on in the presence or absence of l-NAME. There was also increased serum malondialdehyde and decreased E(max) of acetylcholine. Thus simultaneous hypertension and diabetes caused a greater decrease in E(max) of acetylcholine compared to that seen with either diabetes or hypertension alone higher than that seen in hypertension. The blood glucose during GTT was lower than that seen in diabetes groups. Thus simultaneous type 2 diabetes and the SBP was renal hypertension is associated with improved glucose tolerance, but with further deterioration of endothelial dysfunction compared with either condition alone.

Mild heart failure is a mortality marker after a non-ST-segment acute myocardial infarction

BACKGROUND

The Killip classification categorizes heart failure (HF) in acute myocardial infarction, and has a prognostic value. Although non-ST-elevation myocardial infarction (NSTEMI) is increasing steadily, little information is available about the prognostic value of low Killip class in this scenario. Our aim was to assess the prognostic value of mild HF in NSTEMI.

METHODS

835 patients with NSTEMI between 2005 and 2007 were prospectively recruited. Patients in Killip-1 (K1=684) or Killip-2 class (K2=113) were selected (38, with K>2, excluded). Clinical, angiographic, treatment strategies, and 30-day all-cause mortality, together with other cardiovascular outcomes were recorded.

RESULTS

K2 patients were mostly women (K1 27.9% vs K2 48.0%, p<0.001) and older (K1 66.6years vs K2 73.8years, p<0.001) with a higher frequency of diabetes mellitus (p<0.001) and hypertension (p<0.001). Smoking was less frequent in the K2-group (p=0.003). A previous infarction/revascularization history was similar in both groups. The infarction size, assessed by Troponin I/Creatin kinase, did not differ between groups (p=0.378 and p=0.855). Multivessel coronary disease and revascularization procedures were less common in group K2 (p=0.015 and p=0.005 vs group K1, respectively). Patients in K2 had a worse prognosis in terms of maximum Killip class, death and major adverse cardiovascular events (p<0.001). After multivariate analysis, mild HF at presentation was an independent risk factor for mortality (OR=6.50; IC 95%: 2.48-16.95; p<0.001).

CONCLUSION

Mild HF at presentation in NSTEMI is linked to a poor prognosis, with increased short-term mortality. Thus, a more aggressive approach including early cardiac catheterization and revascularization should be considered.