[show abstract][hide abstract] ABSTRACT: Using modern echocardiography, we quantified the extent of global myocardial function and perfusion abnormalities in patients with type 2 diabetes and compared this with the hypothetically similar extent of impairments in patients with coronary artery disease (CAD).
This case-control study (66 patients) compared four age-matched groups: control, type 2 diabetic, CAD, and diabetic subjects with CAD (DCAD) and left ventricular ejection fraction >50%. CAD patients had 1-2 vessel disease. Diastolic and systolic myocardial velocities were assessed with pulsed tissue Doppler. Global myocardial perfusion was assessed with contrast echocardiography as indices of capillary blood volume and myocardial blood flow at maximal vasodilatation. In CAD and DCAD patients, functional and perfusion parameters were additionally assessed in the territory with a normal coronary angiogram reading, providing a model for comparison with the global data from control and diabetic patients.
Comparing diabetic with control subjects, myocardial velocity at early diastole was impaired (8.8+/-1.8 vs 10.1+/-1.7 cm/s; p=0.02) and correlated inversely with age, HbA(1c) and pulse pressure (R (2)=0.761). Capillary blood volume (16.6+/-5.0 vs 24.4+/-4.9%) and blood flow (56+/-35 vs 114+/-40) were decreased (p=0.001). In CAD patients, myocardial velocity at early diastole was similarly decreased (p=0.02). CAD and DCAD patients were receiving more cardiovascular preventive therapy for the same extent of impaired global perfusion as in the less extensively treated diabetes group without CAD (p<0.002), but had superior perfusion of the 'normal' coronary territory than that group (p<0.05).
In patients with diabetes, global diastolic function and myocardial capillary blood volume and blood flow are impaired to the same extent as in patients with CAD. These impairments could form the basis of new therapeutic concepts.
[show abstract][hide abstract] ABSTRACT: The prevalence of type 2 diabetes mellitus is rapidly increasing. Myocardial dysfunction may be a consequence of diabetic cardiomyopathy and it contributes to the poor prognosis of diabetic patients.
This study was designed to test whether tissue Doppler imaging might be a suitable tool for early detection of myocardial dysfunction in diabetic patients.
Forty-three diabetic patients and 33 non-diabetic controls, including age-matched subgroups without evidence of coronary artery disease (n=12), were recruited if they had normal LV-function by standard 2-D echocardiography and no clinical signs of heart failure. They were investigated with tissue Doppler imaging at rest and during pharmacological stress with dipyridamole and/or dobutamine. Myocardial function was calculated as the mean value from six basal myocardial segments for peak velocity at systole (Vs), early diastole (Ve) and atrial contraction (Va).
Compared to controls, diabetic patients had compromised Ve at rest (8.5 +/- 1.7 vs. 9.6 +/- 1.9 cm/sec, p < 0.02), as did the subgroups without coronary artery disease (9.3 +/- 1.7 vs. 10.7 +/- 1.5 cm/sec, p < 0.05). Dobutamine stress resulted in lower Vs (10.7 +/- 2.7 vs. 13.6 +/- 3.4 cm/sec, p < 0.05) and Ve (10.0 +/- 2.1 vs. 13.1 +/- 3.8 cm/sec, p < 0.05) in the diabetic patients, demonstrating an impaired increase of Vs, Vd and Va (p < 0.05, p < 0.0003 and p < 0.03, respectively). An inverse correlation was observed between Ve and age in both control and diabetic individuals. Thus, abnormal values were defined in relation to age.
Diastolic and systolic myocardial dysfunction in patients with type 2 diabetes may be identified by quantitative tissue Doppler imaging before the onset of clinical signs of heart failure and before the appearance of traditional echocardiographic indices of systolic myocardial dysfunction.
[show abstract][hide abstract] ABSTRACT: ST-segment changes and QRS prolongation are electrocardiographic (ECG) markers of myocardial ischemia.
This study was undertaken to investigate the appearance of QRS duration changes with or without concomitant ST-segment changes during a typical anginal episode.
For this purpose, 126 patients underwent 12-lead surface ECG and signal-averaged electrocardiogram (SAECG) during typical anginal pain as well as at the time the patient was asymptomatic. In both periods, QRS duration and ST-segment changes were evaluated. All patients underwent cardiac catheterization.
Of the 126 patients, 108 (86%) had coronary artery disease (CAD), whereas the remaining 18 (14%) patients had normal coronary arteriograms. During typical anginal pain, 75 of the 108 (70%) patients with CAD and 2 of the 18 (11%) patients with normal coronary arteriograms developed QRS prolongation, whereas 60 of the 108 (56%) patients with CAD and 2 of the 18 (11%) patients with normal coronary vessels developed ST-segment changes. Thus, the sensitivities of QRS prolongation measured by SAECG and of ST-segment changes on the surface ECG for the detection of myocardial ischemia were found to be 70 and 56%, respectively, (p < 0.01), whereas the specificities were both found to be 89% (p = NS).
During typical anginal pain, QRS prolongation on the SAECG is more sensitive than are ST-segment changes on the ECG for the detection of myocardial ischemia.
[show abstract][hide abstract] ABSTRACT: Left ventricular non-compaction (LVNC) is a cardiomyopathy considered to be caused by arrest of normal embryogenesis of the endocardium and myocardium. Echocardiography has been the preferred diagnostic procedure; however, the correct diagnosis is often missed or delayed due to the lack of knowledge about this uncommon disease and its similarities to other diseases of the myocardium and endocardium. Here we present two cases: an asymptomatic 39-year-old man who was considered to be suffering from dilated cardiomyopathy (DCM) for four years; and an asymptomatic 19-year-old man who was considered to be suffering from hypertrophic cardiomyopathy. In a recent echocardiography study carried out in our echo lab, we recognized the morphological diagnostic criteria of LVNC. Contrast echocardiography, a low-cost, easy, repeatable, real-time, and non-invasive technique with no ionising radiation, shows a high correlation in the diagnosis of LVNC. In echocardiography, the importance of contrast agents is twofold, as they can be considered essential for a reliable differentiation between the compacted and the non-compacted myocardium, while at the same time they allow accurate measurement of the ratio. Heightened clinical suspicion is necessary for the accurate diagnosis and management of diseases.