Monitoring plasma cardiac troponin I for the detection of myocardial injury after percutaneous transluminal coronary angioplasty.

The objective of this study was to detect myocardial injury defined by an increase of plasma cardiac troponin I (cTnI) following percutaneous transluminal coronary angioplasty (PTCA) and compare plasma cTnI with the risk of cardiac complications at 30 days. Plasma cTnI, creatine kinase (CK) MB, and total CK were determined in 83 patients before (baseline) and 6, 12 and 24 h after PTCA. Thirty-eight patients underwent conventional PTCA, 39 PTCA-stent and six rotational atherectomy. Patients with acute myocardial infarction (AMI) and increased pre-procedural cTnI >0.8 microg/l were categorized into group 1 (n=23). The remaining 60 patients (pre-procedural cTnI=0.8 microg/l) were categorized as follows: group 2 (n=15) AMI; group 3 (n=20) unstable angina (UA); group 4 (n=25) coronary artery disease (CAD). Twelve hours post-procedure, all three cardiac markers were more frequently increased over baseline in group 2 patients (40-60%) compared to patients in group 3 (5-29%, P<0.03) or group 4 (0.5-5%, P<0.01). This was also true for patients undergoing PTCA-stent compared to conventional PTCA or rotational atherectomy (27-40 vs. 4-14%, P<0.02). cTnI was more sensitive (60%) to detect release of myocardial protein after PTCA compared to total CK (47%) or CKMB (43%). A moderate increase of cTnI (0.8-1.5 microg/l) in groups 2, 3 and 4 was associated with higher risk of complications 30 days post-procedure.

Higher prevalence of GPIIIa PlA2 polymorphism in siblings of patients with premature coronary heart disease.

BACKGROUND: The Pl(A2) polymorphism of GPIIIa has been associated with unstable coronary syndromes in some studies, but the association has remained debated. None of the previous studies have focused on families at high risk. Risk factors tend to cluster within kindreds with high prevalence of premature coronary heart disease (CHD). Therefore, a heightened prevalence of the Pl(A2) polymorphism among siblings of patients with CHD would support the hypothesis that Pl(A2) is linked, directly or indirectly, to CHD. OBJECTIVES: To measure the prevalence of the Pl(A2) polymorphism among siblings of patients with CHD before the age of 60 years and to seek an association between the Pl(A2) polymorphism and established atherosclerotic and thrombogenic risk factors. METHODS: From January 1994 to April 1996, we genotyped 116 asymptomatic siblings (60 Caucasians, 56 Afro-Caribbeans) of patients with CHD manifestations before the age of 60 years for the Pl(A) polymorphism (also called HPA-1). A control cohort was used for comparison, consisting of individuals that were matched for race and geographic area but were free of CHD (n = 268, 168 Caucasians and 100 Afro-Caribbeans). In addition, we have characterized the sibling cohort for other atherogenic and thrombogenic risk factors. RESULTS: The prevalence of Pl(A2)-positive individuals (Pl(A2)[+], Pl(A1/A2) heterozygotes plus Pl(A2/A2) homozygotes) in the sibling cohort was high: 41.4%. When analyzed separately, the prevalence of Pl(A2)(+) siblings was 53.3% among Caucasians and 28.6% among Afro-Caribbeans. There was no association between Pl(A2) and other established atherogenic or thrombogenic risk factors. Interestingly, the clustering of other risk factors was lesser among Pl(A2)(+) siblings than their Pl(A1) counterparts. CONCLUSIONS: This study supports the hypothesis that the prevalence of Pl(A2)(+) individuals is high in kindreds with premature CHD. Hence, like the established risk factors that tend to cluster in families with premature CHD and contribute strongly to the accelerated atherosclerotic process affecting these individuals, the Pl(A2) polymorphism of GPIIIa may represent an inherited risk that promotes the thromboembolic complications of CHD. That these asymptomatic Pl(A2)(+) siblings had overall less established risk factors than their Pl(A1) counterparts might represent an explanation for why they remained asymptomatic despite their Pl(A2) positivity.

Painless ischemia provoked by mental stress in the coronary care unit.

A 30-year-old man suffered a cardiac arrest after setting fire to his home. Continuous ST segment electrocardiographic monitoring in the Coronary Care Unit detected painless ST segment depression during an interview with a police officer. At angiography, the patient proved to have severe three-vessel coronary artery disease. This case demonstrates the clinical value of continuous ST segment monitoring in the ICU. In addition, the case illustrates that mental stress is a potential trigger for acute myocardial ischemia in the ICU.