Predictors of myocardial contractile recovery after coronary revascularization in patients with prior myocardial infarction

BackgroundWe sought to explore the prognostic power of certain patient characteristics to predict myocardial contractile recovery after coronary revascularization in patients with prior myocardial infarction.Methods and MaterialsWe enrolled 100 consecutive patients with prior myocardial infarction, significant coronary stenosis/occlusion amenable for revascularization, and regional wall motion abnormality in the distribution of the affected artery. All patients underwent echocardiographic assessment of regional wall motion and left ventricular ejection fraction. Patients underwent coronary revascularization by either percutaneous angioplasty or surgical bypass. Echocardiography was repeated 8 weeks following revascularization. Patients were classified into two groups: Group 1 with evidence of contractile improvement after revascularization at follow-up echocardiography and Group 2 with no such evidence of improvement. The two groups were compared with respect to patients' clinical characteristics and echocardiographic and angiographic data.ResultsPredictors of contractile recovery after revascularization included angina pectoris, the shorter age of infarction at the time of revascularization, a higher baseline left ventricular ejection fraction, a lower baseline wall motion score index, the presence of Grade 2–3 collaterals to the infarct-related artery, and the absence of dyspnea or diabetes mellitus. Stepwise regression analysis identified the presence of Grade 2–3 collaterals to the infarct-related artery and the age of infarction at the time of revascularization as independent predictors of contractile recovery after revascularization.ConclusionsIn patients with prior myocardial infarction, the presence of Grade 2–3 collaterals to the infarct-related artery and the shorter age of infarction at the time of revascularization independently predicted myocardial contractile recovery after coronary revascularization.     

Predictors of contractile recovery after revascularization in patients with anterior myocardial infarction who received thrombolysis

BACKGROUND:

Identification of viable myocardium after myocardial infarction has gained paramount importance with the current progress in coronary revascularization.

OBJECTIVE:

To explore the prognostic power of certain patient characteristics to predict myocardial contractile recovery after revascularization in patients presenting with acute anterior ST elevation myocardial infarction (STEMI) who received thrombolytic therapy.

METHODS:

Seventy-three consecutive patients presenting with first acute anterior STEMI who had received thrombolytic therapy and had significant coronary stenosis or occlusion of the infarct-related artery amenable for revascularization were enrolled. All patients underwent echocardiographic assessment of regional wall motion and left ventricular ejection fraction. Patients underwent coronary revascularization by either percutaneous angioplasty or surgical bypass. Echocardiography was repeated two to three months following revascularization. Patients were classified into two groups: group 1 had evidence of contractile recovery after revascularization at follow-up echocardiography and group 2 had no such evidence of recovery.

RESULTS:

Predictors of contractile recovery after revascularization included a shorter time from symptom onset to the institution of thrombolytic therapy, a lower baseline wall motion score index, the presence of grade 3 collaterals to the infarct-related artery and the use of beta-blockers. Instead, the presence of diabetes mellitus and a totally occluded infarct-related artery predicted poor contractile recovery.

CONCLUSIONS:

Myocardial contractile recovery after revascularization in patients presenting with first acute anterior STEMI may be predicted by the absence of diabetes, a shorter time from symptom onset to thrombolytic therapy, the use of beta-blockers, a lower initial wall motion index score and the presence of collaterals to the infarct-related artery.     

Fistula from coronary arteries to left ventricle after myocardial infarction.

Coronary arteriography and left ventriculography, performed in a 42-year old patient with unstable angina seven months after a myocardial infarct showed communications from both the left anterior descending and right coronary arteries to the left ventricular chamber. The area of communication corresponded to the site of infarction as established by electrocardiogram and left ventriculogram. Whether this is a congenital or acquired lesion is unclear.     

心肌梗死心功能不全患者冠状动脉介入术后心功能恢复的时间进程

目的 探讨心肌梗死心功能不全患者冠状动脉介入术后心功能恢复的时间进程。方法30例左室射血分数（LVEF）<50％的心肌梗死患者,分别于冠状动脉介入术前及术后1周、1个月、3个月检查二维超声心动图,观察室壁节段运动指数（WMSI）和LVEF的变化。结果 心功能改善组于冠状动脉介入术后1个月即出现WMSI和LVEF的改善,至术后3个月继续改善;在心功能改善组中,急性心肌梗死（AMI）患者术后1个月上述指标即有明显改善,而陈旧性心梗（OMI）于术后3个月方有明显改善。结论 有大量存活心肌的心肌梗死心功能不全患者,冠状动脉介入术后心功能恢复呈进行性经过;心肌梗死患者尽早行冠状动脉介入术能使患者心功能及早恢复。     

Dobutamine- vs exercise-induced ST segment elevation early after Q wave myocardial infarction. Prediction of functional recovery after revascularization.

AIMS: The association between stress-induced ST elevation and functional recovery following revascularization after myocardial infarction remains unclear. We assessed the relative accuracy of dobutamine- and exercise-induced ST elevation in Q wave leads in predicting functional recovery following revascularization, and we investigated the relationship of ST elevation to different wall motion responses to dobutamine. METHODS AND RESULTS: Thirty-nine patients underwent dobutamine stress echo and exercise test 8+/-2 days after Q wave myocardial infarction. All patients underwent angiography and subsequent revascularization. Follow-up echocardiograms were obtained 7+/-4 weeks after revascularization. Functional recovery was assessed by the difference between the baseline and the follow-up asynergy index. Nineteen patients (48%) developed dobutamine- and exercise-induced ST elevation. There was significant agreement between the tests (k=0.58, P<0.001). We found a significant correlation between dobutamine and exercise-induced ST elevation with functional recovery following revascularization (r=0. 45, P<0.005 and r=0.7, P<0.001, respectively). The parameters with the highest predictive value for functional recovery were: (a) the biphasic response during dobutamine infusion, (b) the development of ST elevation in both tests, and (c) the development of exercise-induced ST elevation in more than three leads. CONCLUSION: There is a strong association between dobutamine- and exercise-induced ST elevation with functional recovery following revascularization. Exercise-induced ST elevation in more than three leads and a biphasic response during dobutamine infusion accurately predict functional recovery.     

Decompression of the left ventricle in the recovery period during myocardial revascularization

Effective left heart decompression is essential for the reduction of myocardial oxygen consumption during recovery from an induced ischemic insult. During the early postischemic recovery phase of patients undergoing aorto-coronary bypass surgery, left ventricular, left atrial and aortic pressures were measured in non-vented hearts and in 2 types of left ventricular decompression. The following findings were made: Total cardiopulmonary bypass with effective decompression of the left ventricle decreases peak systolic left ventricular pressure, thereby reducing oxygen consumption of the myocardium. In this way adequate conditions are provided for recovery of the myocardium after unclamping of the aorta. The best method for decompression appears to be the placing of a large-lumen cannula in the left ventricle and allowing the blood to pour freely from the vent. The zero or near zero left ventricular filling pressure achieved with total cardiopulmonary bypass but without ventricular decompression does not prevent the chamber from producing isometric pressure work with peak systolic pressure reaching 80 to 90 torr. The hazard of air embolism may be reduced by precautionary measures. Left atrial monitoring permits recognition of pressure decreases to negative values. Active suction of the blood from the left ventricle is dangerous and should be avoided.     

Usefulness of myocardial contrast echocardiography in predicting global left ventricular functional recovery after anterior wall acute myocardial infarction

Although multiple recent studies have shown that myocardial contrast echocardiography (MCE) reliably differentiates between regional stunning and necrosis after acute myocardial infarction (AMI), prognosis is more closely related to measures of global left ventricular systolic function. One hundred fifteen patients underwent baseline wall motion assessment and MCE 2 days after admission and follow-up echocardiography a mean of 69 days later. Good agreement was found between perfusion score index and follow-up wall motion score index, indicating that MCE performed early after anterior wall AMI may be clinically useful in routine post-AMI risk stratification.     

Status of the coronary arteries and left ventricle of patients surviving myocardial infarction

The condition of coronary arteries and left-ventricular function were assessed in 62 patients with a history of myocardial infarction 1 month to 4 years prior to coronarographic investigation. It was demonstrated that the detectability of an occlusion in the artery supplying blood to the infarcted area decreased with time elapsed since myocardial infarction, the correlation being more characteristic of the anterior interventricular branch of the left coronary artery. An analysis of ventriculograms showed that myocardial infarction due to a lesion of the left coronary artery results in a smaller left-ventricular dysfunction and is less commonly associated with circulatory insufficiency. The frequency of spontaneous thrombolysis is shown to be relatively high in postmyocardial-infarction patients.     

Surgical reconstruction of left ventricle after anterior myocardial infarction in both women and men

BACKGROUND: Differences between men and women in the prevalence and clinical course of coronary artery disease (CAD) have been well documented. There are no data in literature on the differences between males and females in the incidence of post-infarction left ventricular (LV) wall motion abnormalities of akinesia/dyskinesia type and the outcome after surgical LV reconstruction. AIM: To compare gender-related differences in clinical characteristics, distribution of LV wall motion abnormalities, and outcome after surgical LV reconstruction. METHODS: Between 1993 and 2000, 3119 patients underwent surgery for CAD in our institution. Coronary artery bypass grafting (CABG) was performed in 3033 patients. Of those, 86 (2.67%) underwent CABG with concomitant surgical ventricular restoration (SVR). Clinical, echocardiographic and procedural data were compared between females and males. RESULTS: In the SVR group, the percentage of women was significantly higher than in the CABG group (29% vs 18.5%, p=0.05). Obesity, unstable angina and pulmonary oedema were significantly more common in females than in males. The end-diastolic volume and global ejection fraction were lower in women than in men. The ratio of ANV (systolic volume of akinetic/dyskinetic zone of LV) to EDV (diastolic LV volume) was significantly higher in females than in males. Cardiac output, cardiac index and stroke volume were significantly lower in females. Women had significantly higher NYHA class. Because of the greater extent of LVA in women, patch plasty was performed significantly more often in females than in males (p=0.05). Mortality in both genders was similar (4% vs 3%, NS). After the operation, a significant improvement of LV function was found in both groups, but the degree of improvement was higher in women. CONCLUSIONS: There is male predominance, both in the CABG and SVR groups, however, the proportion of females in the SVR group is significantly greater than in the whole CABG group. LV function is more depressed and NYHA class is higher in females than males. Because the extent of LV akinesia and dyskinesia is greater in females than in males, the circular plasty with patch closure is required more often in women.     

Hyperoxemic perfusion of the left anterior descending coronary artery after primary angioplasty in anterior ST-elevation myocardial infarction.

OBJECTIVES: To assess left ventricle function recovery, ST-segment changes, and enzyme kinetic in ST-elevation myocardial infarction patients treated with intracoronary hyperoxemic perfusion (IHP) after primary percutaneous coronary intervention and compare them with the results obtained in control patients. BACKGROUND: IHP has been shown to attenuate microvascular reperfusion injury, which may result in poor LV function recovery despite successful primary percutaneous coronary intervention. METHODS: Twenty seven anterior ST-elevation myocardial infarction patients treated < or = 12 hr after symptom onset by primary percutaneous coronary intervention were subjected to selective IHP into the left anterior descending coronary artery for 90 min. They were compared with 24 anterior ST-elevation myocardial infarction control patients matched in clinical and angiographic characteristics and treated with conventional primary percutaneous coronary intervention. Left ventricular function recovery was evaluated by serial 2D contrast echocardiography. RESULTS: Left anterior descending coronary artery recanalization was successful in all patients. After IHP (100% successful, duration 90 +/- 5.4 min), patients showed a 4.8 +/- 2.2 hr shorter time-to-peak creatine kinase release (P = 0.001), a shorter creatine kinase half-life period (23.4 +/- 8.9 hr vs. 30.5 +/- 5.8 hr, P = 0.006), and a higher rate of complete ST-segment resolution (78% vs. 42%, P = 0.01). A significant improvement of mean left ventricular ejection fraction (from (44 +/- 9)% to (55 +/- 11)%, P < 0.001) and wall motion score index (from 1.77 +/- 0.2 to 1.39 +/- 0.4, P < 0.001) was observed at 3 months in IHP patients only. CONCLUSION: After successful primary coronary intervention, IHP is associated with significant left ventricular function recovery when compared to conventional treatment. Enzyme kinetic and ST-segment changes suggest faster and more complete microvascular reperfusion and may explain the salutary effects of this new therapy on left ventricular function.     

Ultrasonic integrated backscatter discloses intramyocardial hemorrhage in patients with acute myocardial infarction

BACKGROUND: It has been reported that intramyocardial hemorrhage (IH) can be detected by magnetic resonance imaging (MRI) and IH correlates with the poor prognosis of acute myocardial infarction (AMI). We examined whether integrated backscatter (IBS) can disclose IH in patients with AMI. We recorded IBS images in 34 patients with AMI who underwent coronary angioplasty within 12 hours of symptom onset. METHODS: We measured calibrated IBS (C-IB) and cyclic variation (CV) in the center of the risk area on the third day after reperfusion. C-IB was calculated as: average IBS value of risk area--average IBS value of intraventricular blood. MRI was performed within 3 days after reperfusion. Regional wall motion score index (RWMSI) was calculated as follows: sum of scores (0 - 4) in risk area/number of segments of risk area. We evaluated left ventricular function using RWMSI shortly and one month after reperfusion. RESULTS: RWMSI in the IH group (12 cases) was significantly higher than in the non-IH group (2.3+/-0.5 vs. 1.8+/-0.6: P<0.01) one month later, while RWMSI in both groups was almost the same shortly after reperfusion. The IH group showed a significantly higher value of C-IB than the non-IH group (18.6+/-2.0 vs. 16.0+/-1.4: P<0.01), while there were no significant differences in CV values between two groups. Using 17 as a cutoff value of C-IB, C-IB can detect IH with 92% sensitivity and 91% specificity. Using both CV and C-IB, however, IH can be detected more specifically. CONCLUSION: Ultrasonic IBS, especially C-IB, discloses intramyocardial hemorrhage in patients with reperfused AMI.     

Individual prediction of functional recovery after coronary revascularization in patients with ischemic cardiomyopathy: the scar-to-biphasic model

Currently, the prediction of improvement of left ventricular (LV) ejection fraction (EF) after revascularization in patients with ischemic cardiomyopathy relies only on viable myocardium extent, whereas both the amount of viable and scar tissue may be important. A model was developed, based on the amount of viable and nonviable myocardium, to predict functional recovery. Viable and scarred myocardium was defined by dobutamine stress echocardiography (DSE) in 108 consecutive patients. LVEF before and 9 to 12 months after revascularization was assessed by radionuclide ventriculography; an improvement of ≥5% was considered significant. In the 1,089 dysfunctional segments (63%), DSE elicited biphasic response in 216 segments (20%), sustained improvement in 205 (19%), worsening in 43 (4%), and no change in 625 (57%). LVEF improved in 39 patients (36%). Only the numbers of biphasic and scar segments were predictors of improvement or no improvement of LVEF (odds ratio 1.5, 95% confidence interval 1.2 to 1.7, p <0.0001 for biphasic segments; odds ratio 0.8, 95% confidence interval 0.7 to 0.9, p <0.0005 for scarred segments). The sustained improvement and worsening pattern were not predictive of improvement or no improvement. A regression function, based on the number of scar and biphasic segments, showed that the likelihood of recovery was 85% in patients with extensive biphasic tissue and no scars and 11% in patients with extensive scars and no biphasic myocardium. Patients with a mixture of scar and biphasic tissue had an intermediate likelihood of improvement (50%). In patients with ischemic cardiomyopathy and a mixture of viable and nonviable tissue, both numbers of viable and nonviable segments should be considered to accurately predict functional recovery after revascularization.     

Delayed recovery of left ventricular regional work after coronary angioplasty in patients with opposite wall old myocardial infarction

 To evaluate the changes in left ventricular (LV) regional function during acute ischemia in patients with opposite wall old myocardial infarction (OMI), we examined LV regional work during percutaneous transluminal coronary angioplasty (PTCA) of the left anterior descending artery (LAD) in patients with a posterior OMI. Twelve patients with normal LV contraction (group A) and six patients with posterior OMI (group B) who were scheduled to undergo PTCA were enrolled in this study. All patients had single-vessel coronary artery disease and no collateral circulation. Sixty-second inflation was performed, and data were collected every 10 s. The regional work was calculated from the relationship between the mean wall stress and area strain. Regional work of the interventricular septum decreased after balloon inflation and was at its minimum at the end of inflation (group A: 0.6 ± 0.3 mJ/cm³; group B: 0.8 ± 0.4 mJ/cm³). After balloon deflation, the septal regional work increased in both groups, and recovered to baseline at 40 s in group A and at 60 s in group B. Regional work of the posterior wall increased in group A after balloon inflation, but not in group B. The recovery of LV regional work after PTCA is delayed in patients with opposite-wall OMI. Received: March 2, 2002 / Accepted: January 25, 2003     

Combined use of dobutamine echocardiography and myocardial contrast echocardiography in predicting regional dysfunction recovery after coronary revascularization in patients with recent myocardial infarction

BACKGROUND: Myocardial contrast echocardiography and dobutamine echocardiographyhave recently emerged as potentially useful clinical tools todetect reversible myocardial dysfunction. However, the relativeaccuracy of these two techniques in predicting regional wallmotion improvement after coronary interventions is still unclear.The aim of the present study was to compare their diagnosticvalue in predicting functional recovery after coronary revascularizationin patients with recent acute myocardial infarction. METHODS AND RESULTS: Twenty-four patients with acute myocardial infarction underwentmyocardial contrast echocardiography and dobutamine echocardiographywithin 2 weeks of hospital admission. Infarct zone contrastscore and wall motion score indexes were derived in each patient.Infarct-related artery revascularization was performed beforehospital discharge in all selected patients. Resting echocardiographywas repeated 3 months after revascularization, and regionalfunction recovery was analysed. The degree of wall motion scoreimprovement at 3-month follow-up and the percentage of positiveresponses to dobutamine echo were greater (P<0·001and P<0·002, respectively) in patients with a higherbaseline contrast score (0·50). Conversely, no significantchanges were observed either during dobutamine echo or afterrevascularization in the group of patients without residualperfusion within the infarct area. Diagnostic agreement betweenboth techniques in predicting reversible dysfunction was high(81% of segments). The sensitivity and negative predictive valuein predicting functional outcome were 100% (95% confidence interval[CI], 87% to 100%) and 100% (95% CI, 93% to 100%) by contrastecho, and 85% (95% CI, 66% to 96%) and 93% (95% CI, 84% to 98%)by dobutamine echo. The specificity and positive predictivevalue were 90% (95% CI, 80% to 96%) and 81% (95% CI, 64% to93%) by contrast echo, and 88% (95% CI, 78% to 95%) and 76%(95% CI, 58% to 90%) by dobutamine echo. The combination ofmyocardial contrast and dobutamine echocardiography positiveresponses improved specificity and positive predictive valuein detecting functional recovery after revascularization to100% (95% CI, 94% to 100%) and 100% (95% CI, 85% to 100%), respectively.However, the sensitivity and negative predictive value slightlydecreased with the use of both methods (85% [95% CI, 66% to96%)] and (93% [95% CI, 85% to 98%)], respectively. CONCLUSIONS: In patients with recent myocardial infarction, reversible dysfunctionafter coronary revascularization and the response to dobutamineinfusion are strictly dependent on microvascular integrity.However, microvascular perfusion does not always imply functionalrecovery after coronary revascularization. The integration withdob utamine echo results seems particularly helpful to furtherimprove myocardial contrast echo specificity and positive predictivevalues.     

Predictors of right ventricle dysfunction after anterior myocardial infarction

Background

Regardless significant therapeutic advances, mortality and morbidity after myocardial infarction (MI) are still high. For a long time, the importance of right ventricle (RV) function has been neglected. Recently, RV dysfunction has also been associated with poor outcomes in the setting of heart failure. The shape, location, and contraction conditions make the RV chamber assessment technically challenging.

Methods

Our study identified clinical characteristics and left ventricle (LV) echocardiographic data performed 3-5 days after MI that could be associated with RV dysfunction (RV fractional area change [FAC] < 35%) 6 months after MI.

Results

The RV dysfunction group consisted of 11 patients (RV FAC 29.4% ± 5.2) and the no RV dysfunction group of 71 patients (RV FAC 43.7% ± 5.1); (P < 0.001). Both groups presented the same baseline clinical characteristics. Left atrium (LA), interventricular septum (IVS), and left ventricular posterior wall (LVPW) were larger in RV dysfunction than in no RV dysfunction. Conversely, E wave deceleration time (EDT) was lower in RV dysfunction when compared with no RV dysfunction. Left atrium_adj (adjusted by gender, age, infarct size, and body mass index) (odds ratio [OR], 1.22; confidence interval [CI], 1.016-1.47; P = 0.032), interventricular septum_adj (OR, 1.49; CI, 1.01-2.23; P = 0.044), and E wave deceleration time_adj (OR, 0.98; CI, 0.97-0.98; P = 0.029) assessed soon after MI predicted RV failure after 6-months.

Conclusions

LV diastolic dysfunction, resulting from anterior MI and assessed 3-5 days after the event, may play an important role in predicting RV dysfunction 6 months later.