Predictors of left ventricular thrombus formation in patients with anterior myocardial infarction: role of activated protein C resistance

Mean Platelet Volume in Patients With Dilated Cardiomyopathy

We assessed the clinical echocardiograhic, hematological, and biochemical parameters in patients with dilated cardiomyopathy (DCMP) and control individuals mainly focusing on the mean platelet volume (MPV) in terms of DCMP and left ventricle (LV) thrombus formation. Consecutive patients (n = 251) with DCMP and 266 patients without DCMP were studied. Mean platelet volume was significantly greater in patients with DCMP than in control patients ( P < .05 for all comparisons). Comparing DCMP patients with LV thrombus (19 patients, 8%) and without LV thrombus (232 patients, 92%) showed that the prevalence of smokers was significantly higher and ejection fraction was significantly lower in patients with LV thrombus. We have shown that patients with DCMP have significantly higher MPV suggesting more platelet activation and the MPV of patients with DCMP and LV thrombus is comparable to those of patients without LV thrombus.

Activation of coagulation system in dilated cardiomyopathy: comparison of patients with and without left ventricular thrombus

OBJECTIVES

We aimed to investigate plasma levels of molecular markers for platelet activity, thrombin activation and fibrinolytic status in patients with dilated cardiomyopathy (DCM) with and without left ventricular (LV) thrombus and to compare these markers between patients with DCM and control participants.

MATERIALS AND METHODS

The study population comprised 60 patients with DCM who met the inclusion criteria. Patients were divided into two groups: 22 patients with LV thrombus and 38 patients without LV thrombus. The age-matched control group consisted of 23 healthy participants (18 men and five women with a mean age of 49). Patients with DCM and healthy participants were compared with respect to platelet activity, thrombin activation and fibrinolytic status. These comparisons were also performed in patients with DCM with and without LV thrombus.

RESULTS

Platelet factor 4 (28.2+/-4.4 ng/ml compared with 20+/-3.1 ng/ml, P<0.01) and beta-thromboglobulin (40+/-2 ng/ml compared with 17+/-3 ng/ml) levels, reflecting platelet activity, were significantly higher in patients with DCM than in control participants. Fibrinopeptide A (6.94+/-0.69 ng/ml compared with 1.96+/-0.1 ng/ml, P<0.001) and thrombin-antithrombin III complex (5.26+/-2.60 ng/ml compared with 3.17+/-1.23 ng/ml, P<0.001) levels, as markers of fibrin generation, were also higher in patients with DCM than in normal participants. Plasma levels of D-dimer (118+/-16 ng/ml compared with 85+/-3 ng/ml, P<0.001) and plasmin-alpha2-plasmin inhibitor complex (0.8+/-1.1 microg/ml compared with 0.6+/-1.7 microg/ml, P<0.001) in patients with DCM significantly exceeded those in the normal participants. There were no statistically significant differences between patients with and without LV thrombus in DCM with respect to platelet activity, thrombin activation and fibrinolytic status.

CONCLUSION

We have shown that platelet activation, thrombin activation and fibrinolytic activity are increased in patients with DCM compared to control participants. However, these markers reflecting coagulation activation in patients with LV thrombus are comparable to those in patients without LV thrombus.

Predictors of left ventricular thrombus formation in patients with dilated cardiomyopathy: role of activated protein C resistance

OBJECTIVES

The aim of this study was to investigate the association between left ventricular thrombus formation and natural anticoagulant systems including the protein C, protein S and antithrombin in patients with dilated cardiomyopathy.

MATERIALS AND METHODS

Sixty patients with dilated cardiomyopathy who met the inclusion criteria were included in the study. Patients were divided into two groups: group I consisted of 22 patients with left ventricular thrombus and group II consisted of 38 patients without left ventricular thrombus. Our main inclusion criteria were ejection fraction </= 35% and left ventricular end-diastolic diameter >/= 6.0 cm. These two groups were compared for clinical and hematologic parameters (activated protein C resistance, protein S and antithrombin).

RESULTS

There were no statistically significant differences between patients with or without left ventricular thrombi with respect to left ventricular end-diastolic and end-systolic dimensions, ejection fraction, fractional shortening and left atrial diameter. There were no statistically significant differences between patients with and without left ventricular thrombus with respect to platelet count (252 +/- 64/mm3 x 10(3) compared with 260 +/- 74/mm3 x 10(3) respectively, P=0.68), prothrombin time (12.94 +/- 1.9 s compared with 12.86 +/- 1.3 s respectively, P=0.82), activated partial thromboplastin time (32 +/- 5 compared with 30 +/- 4 s respectively, P=0.32) and fibrinogen levels (36 +/- 9 mg/dl compared with 34 +/- 8 mg/dl respectively, P=0.41). None of the patients had protein S and antithrombin deficiency. Activated protein C resistance was found in 12 patients (12 out of 22, 54%) in group I and four patients (four out of 38, 9.5%) in group II (P < 0.01). It was also shown to be an independent predictor of left ventricular thrombus (P < 0.05).

CONCLUSION

Activated protein C resistance is found to be an independent predictor of left ventricular thrombus in patients with dilated cardiomyopathy who have ejection fractions less then 35% and left ventricular end-diastolic dimensions > 6.0 cm.

Left ventricular apical thrombus formation in a patient with suspected tako-tsubo-like left ventricular dysfunction

A 74-year-old woman with hypertension and bronchial asthma had chest discomfort at rest and 4 days later was admitted to her nearby hospital because of the sudden onset of right hemiparesis. The hemiparesis had almost disappeared within 24 h of onset, but because an electrocardiogram showed sinus tachycardia and diffuse symmetrical T-wave inversion, she was referred for cardiac examination. Coronary angiography did not reveal any significant coronary artery stenosis, but left ventriculography revealed severe hypokinesis of the left ventricular apical region, which contained a 4 x 4-mm solid thrombus moving freely with a wavy motion. Moreover, the activity of both protein C and protein S had decreased. The thrombus disappeared after 2 weeks of anticoagulant treatment with warfarin. Her clinical course suggested that the transient cerebral ischemic attack was caused by embolism of the left ventricular thrombus associated with 'tako-tsubo-like left ventricular dysfunction'.