Wall motion changes in myocardial infarction in relation to the time elapsed from symptoms until revascularization.

OBJECTIVE: Wall motion abnormalities during acute ST-segment elevation myocardial infarction (STEMI) and the improvement after recanalization depend on the conditions of the coronary occlusion. METHODS: Fifty-seven patients with first-ever STEMI due to one-artery occlusion, treated with primary PCI, were evaluated. Area at risk and left ventricular wall motion abnormalities were localized with coronary angiography and echocardiography and then compared in relation to the time elapsed from the onset of symptoms at the time of infarction and at 3 months. Left ventricular diameters and ejection fractions were evaluated in relation to the ischemic time. RESULTS: Three hundred forty-one affected left ventricular segments were detected with angiography, while echocardiography showed 206 segments with motion abnormality. No correlation was found between the regional wall motion index in the area at risk and the time elapsed from the beginning of symptoms. However, the improvement in wall motion abnormalities at the follow-up was dependent on the ischemic time (r=-0.29, p<0.03). The early subgroup showed significant improvement in left ventricular ejection fraction at follow-up (p=0.03), whereas in the late subgroup, a significant increase in left ventricle diameters was observed. CONCLUSION: Our results first demonstrate in humans that in the early hours from the occlusion of the coronary artery, the extent and severity of the wall motion abnormalities inside the area at risk show large variability without relation to the elapsed time since the onset of symptoms. On the other hand, the results of follow-up echocardiography proved that the wall motion improvement was highly dependent on the ischemic time.

Holistic polar map for integrated evaluation of cardiac imaging results.

Polar map display (PM) is a comprehensive interpretation of the left ventricle. This is a non-rigid registration of the left ventricle originally for the visual and quantitative analysis of tomographic myocardial perfusion scintigrams. In this scheme the maximal-count circumferential profiles of well-defined short- and long-axis planes are plotted to a map showing the distribution of the perfusion tracer onto a two-dimensional polar representation. The usual coronary artery distribution is often indicated on the PMs of SPECT studies by referring to the regions of the three main coronary branches, nevertheless, the individual variations may differ extensively. We set out to develop an Access (Microsoft)-based computer program that permits an integrated evaluation of the imaging results (coronary angiography, echocardiography and SPECT) on patients with coronary artery disease. This semi-quantitative registration of the coronary tree to a PM focused on the relation between the supplying coronary branches and the myocardial regions of the 16-segment left ventricular evaluating model. All the recorded anatomical and functional data were related to these 16 left ventricular segments, which allowed the direct comparison and holistic synthesis of the results. Two projections were taken into consideration for generation of the coronary PM: from the right anterior oblique projections, the left anterior descendent (LAD)/right coronary artery (RCA) border was assessed through the comparison of the left and right coronary angiograms. The terminations of the visually detected end-arteries showed the separation of the myocardial beds supplied by the two branches. The border of the myocardial beds on the polar map was determined on the "vertical axis" of the local coordinate system. The RCA/ left circumflex (LCx) separation can be determined from the left anterior oblique view. In this projection, the left ventricular septal edge was delineated by the LAD, while the LCx indicated the lateral epicardial surface. The individual coronary artery circulation was typified from among 12 variations in the Holistic Coronary Care program. With this determination of the individual coronary circulation, the lesion-associated segments are generated automatically by the software. The lesion-associated regions are defined as the myocardial bed of a diseased artery distal to the lesion. The PMs generated from the coronary angiographic results were compared with those of 99Tc-labelled MIBI single photon emission computed tomography (SPECT) in order to test the accuracy of the localizing method. The overlap between the segments associated with the coronary lesion and the stress perfusion defects (<80% relative MIBI activity during stress tests) was analyzed in 10 patients with (sub)total coronary occlusion after myocardial infarction. The distributions of the segments with stress perfusion defects on MIBI SPECT gave positive and negative predictive values of coronary occlusion of 0.94 and 0.8, respectively. According to the 16-segment wall motion analysis by echocardiography, the positive and negative predictive values of coronary occlusion for wall motion abnormality were 0.82 and 0.76, respectively. While the distal part of the subtended region usually demonstrated a higher degree perfusion abnormality than the proximal part, the high positive predictive value proved that, during the stress condition, the perfusion defect could be detected in practically all the subtended regions. The low negative predictive value of the coronary lesion for the wall motion abnormality was associated with the remodeling of the entire left ventricle.

Diastolic function of the heart in mixed connective tissue disease.

The authors examined the right and left ventricle functions in patients with mixed connective tissue disease (MCTD) by Doppler echocardiography. Of 51 patients, 20 had temporary pulmonary arterial hypertension in their case history. According to our knowledge, this is the first study examining the use of Doppler echocardiography and tissue Doppler technique in MCTD patients. Of 51 MCTD patients, 20 had pulmonary arterial hypertension (PAH) in the past 2 years. Diameters of the right and left ventricle, systolic and diastolic blood pressure were measured both in the 51 MCTD patients and in the 30 control subjects (mean age 54.8+/-6.2 years in the case of patients and 54.2+/-8.8 years in the case of control subjects). To estimate the global ventricle functions, the myocardial performance index--as described by Tei et al. (J Am Soc Echocardiogr 6:838-874, 1996)--was applied, which reflects the ratio of the sum of the isovolumetric contraction and relaxation time as compared to the ejection time. The 20 MCTD patients with PAH received cyclophosphamide therapy for 1 year beside the pulse corticosteroid (CS) therapy. In the case of MCTD patients without PAH, different treatments were used: 12 out of 31 patients were treated with sulfasalazine, 5 of whom received a combination of CS and methotrexate, and 14 took nonsteroid antiinflammatory drugs. In the case of the 51 MCTD patients (20 with PAH and 31 without PAH), diastolic function disorder of the left ventricle was detected; the diastolic Ee/Aa velocity quotient of the lateral mitral anulus was lower (p<0.01), and the mean deceleration time was longer (p<0.001) than that of the control group. The Tei index demonstrated the damage of the global ventricle function. The Tei index of the right ventricle indicated global failure of the right ventricle function in the case of MCTD patients complicated with PAH (Tei index 0.36+/-0.07 in MCTD with PAH and 0.28+/-0.04 in MCTD without PAH, p<0.001). The right ventricle function of MCTD patients without PAH was no different from that of the control group. In the case of patients with MCTD, signs of the disorder of the left ventricle diastolic function were observed. Our results suggest that the global impairment of the left ventricle function is the consequence of the disease itself and not the side effect of the treatment. In the case of MCTD patients complicated with PAH, the signs of the right ventricle function impairment proved to be permanent.

[Left ventricular systolic and diastolic function and dysfunction]. / Systolés és diastolés funkció és diszfunkció.

The left ventricular systolic function--independently from the type of cardiac disease--determines the quality of life and the prognosis of the patients, so the examination of this parameter is indispensable. To measure it accurately is difficult, because the muscle fibers in the ventricular wall run partly circumferentially, partly longitudinally and tangentially and we have not any kind of method, which could have examined the function all of these differently contracting myocardial muscle fibers. To add these, the shape of the left ventricle is geometrically irregular, all ventricular segments move toward a "gravitational point" during the systole and backward during the diastole, and the heart also has a rotational motion in the chest during every cardiac cycle. Haemodynamic parameters (preload, afterload, heart rate and synchronous or asynchronous motion of the left ventricular walls) also can modify the left ventricular function. The ejection fraction is most frequently measured by echocardiography. M-mode, 2-dimensional, 3-dimensional echocardiography, Doppler methods, Doppler Myocardial Imaging (DMI), contrast echocardiography and color kinesis can be used to get more precise information about the left ventricular systolic function. The diastolic left ventricular function can be analysed using the mitral Doppler curve. The DMI, Strain Rate Imaging (SRI), contrast echocardiography and color kinesis improve the quality of imaging and so the accuracy of measurement. Using Doppler Myocardial Imaging and Strain Rate Imaging we can get information about the global and segmental left ventricular systolic and diastolic function. These parameters are well reproducible, and that is why they can be used in the assessment of the efficacy of pharmaceutical or other therapeutical procedures and following the changes in the clinical state of the patients.

99mTc-MIBI SPECT assessment of the effects of aneurysm resection on the left ventricular morphology.

OBJECTIVE: 99mTc-MIBI SPECT is a widely used myocardial perfusion investigation technique, but few data are available concerning its use to assess the morphological characteristics of a left ventricular aneurysm (LVA) before and after LVA resection. METHODS AND RESULTS: Pre- and postoperative rest 99mTc-MIBI SPECT images were analysed in order to characterize the features of LVAs and the changes in the 3D scintigraphic parameters after apical LVA resection in 6 patients. In the middle horizontal slice an angle was defined to quantify the apical divergence associated with the LVA. After resection, the changes in the divergence angles (DA) were measured as were the changes in the left ventricular volumes (LVV) by volumetric calculations. The mean DA decreased from an average of 38.50 degrees +/- 11.32 degrees preoperatively to 24 degrees +/- 11.84 degrees postoperatively (p = 0.03). The mean LVV also decreased significantly: from 443 +/- 87 ml to 317 +/- 74 ml (p = 0.003). The resectable LVAs were associated with a very low isotope uptake in the apical segments (< 20% relative activity). A DA < 20 degrees was also characteristic of anatomical LVA in all patients. A regression curve plotting divergence angle and the number of left ventricular segments below 20% relative activity showed a significant correlation between them (r = 0.86, p = 0.003). CONCLUSIONS: The significant decreases of DA and LVV after resection reflect favourable morphological changes in the left ventricle (reverse remodelling). We consider 99mTc-MIBI SPECT a useful method for apical LVA detection, it allows an analysis of the morphological (and indirectly the functional) results of the surgery.

Effects of long-term transdermal nitrate treatment on left ventricular function in patients following myocardial infarction.

BACKGROUND: [corrected] Nitrates are widely used for the treatment of myocardial infarction (MI). The large megatrials (GISSI-3 and ISIS-4) did not in fact demonstrate a significant decrease in mortality in the nitrate-treated group. However, examination of the number of postinfarction angina episodes and the occurrence of cardiogenic shock in the GISSI-3 study did reveal significant decreases. HYPOTHESIS: It was hypothesized that chronic nitrate treatment after an MI preserves left ventricular systolic and/or diastolic functions. METHODS: Patients were divided into two groups: those receiving chronic nitrate treatment for 6 months after an MI (n = 30), and those without such treatment (n = 29). Echocardiography was performed 3, 14, 42, and 180 days after the infarction. The changes in early diastolic and atrial contraction-related mitral valve inflow pattern and deceleration time were assayed. Alterations in systolic, diastolic, and atrial reverse flow velocities in the pulmonary vein were measured, as were ejection fraction (EF), the number of registered angina episodes, and the maximal ST-segment depression in response to the stress test. RESULTS: During the 6-month study period, the increase in systolic pulmonary venous flow velocity was significantly larger in the nitrate group than in the controls. The decreases in the velocities of the diastolic and the atrial reverse flow were also more pronounced in the nitrate group than in the controls. The EF was improved only in the nitrate group. Examination of the maximal ST-segment depression in response to the stress test revealed a significant decrease in the nitrate group only. There were no significant differences between the two groups in the number of registered angina episodes or mitral inflow pattern. CONCLUSIONS: The study showed that prolonged nitrate treatment after an MI may help preserve diastolic left ventricular function.