Noninvasive assessment of left and right ventricular filling in myocardial infarction with a two-dimensional Doppler echocardiographic method

Inflow characteristics of left and right ventricular filling were assessed in 40 patients with myocardial infarction and in 10 normal subjects by pulsed Doppler echocardiography. Patients with myocardial infarction were subdivided into four groups, focusing on the involvement of right ventricular and septal branches of the coronary arteries. Group I consisted of 11 patients with anterior infarction who showed an obstructive lesion of the proximal left anterior descending branch involving the first septal perforator with a patent right coronary artery. Group II consisted of 10 patients with inferior infarction who showed an obstructive lesion of the proximal right coronary artery involving the right ventricular branch. Group III consisted of 12 patients with both anterior and inferior infarction who showed obstructive lesions of both the proximal left anterior descending branch and the right coronary artery involving the right ventricular branch. Group IV consisted of seven patients with lateral infarction who showed an obstructive lesion of the diagonal branch or branches of the circumflex coronary artery with a patent left anterior descending branch and right coronary artery. Three measurements were performed from the transmitral and transtricuspidal inflow velocity patterns to assess the left and right ventricular diastolic behaviors. These measurements were: acceleration half-time, deceleration half-time of early diastolic rapid inflow, and the ratio of the peak velocity of early diastolic rapid inflow to that of the late diastolic inflow due to the atrial contraction. Impaired diastolic filling of the left ventricle compensated by enhanced left atrial contraction was observed in patients with myocardial infarction from groups I, II, III and IV.(ABSTRACT TRUNCATED AT 250 WORDS)     

Anterior ST-segment elevation with right coronary artery occlusion: a unique case of isolated right ventricular infarction

Anterior ST-segment elevation is the classic electrocardiographic feature of anterior left ventricular myocardial infarction due to occlusion of the left anterior descending artery. However, anterior ST-segment elevation has also been described in patients with right coronary artery occlusion, in whom concomitant inferior ST-segment elevation is also typically present. A case of proximal right coronary artery occlusion resulting in anterior ST-segment elevation without inferior ST-segment elevation is reported in this article. It is hypothesized that the inferior left ventricular wall was protected by left-to-right collaterals, as seen on coronary angiography, with resultant isolated right ventricular infarction upon proximal right coronary artery occlusion. In conclusion, this report presents a unique case of an isolated right ventricular infarction resulting in an electrocardiographic pattern mimicking anterior-wall left ventricular infarction.     

Right ventricular infarction: role of the moderator band artery in determining infarct size

We studied 19 patients with proximal right coronary artery occlusions associated with acute myocardial infarcts less than 30 days old. Right ventricular infarct size, determined as a percentage of right ventricular surface area, ranged from 0% to 29%. Correlation of 24 variables measuring infarct size, chamber size and coronary artery disease failed to demonstrate a significant correlation with the extent of right ventricular infarction. However, estimates of the degree of obstruction to potential collateral flow into the right coronary arterial system from the left anterior descending coronary artery, especially through the moderator band artery, showed a significant positive correlation with infarct size (p less than 0.02). Among the five patients with massive (greater than 25%) right ventricular infarction, four had significant (greater than 75%) obstruction of the left anterior descending system, resulting in potentially impaired collateral blood flow; the other patient had normal coronary arteries and embolic occlusion of the proximal right coronary artery with contraction band necrosis. The study suggests that collateral flow to the right ventricular myocardium, especially through the moderator band artery, protects against massive infarction in the presence of proximal right coronary artery occlusion.     

Anterior ST-segment deviation during inferior myocardial infarction: arteriographic correlations during the acute phase

Electrocardiographic changes in the anterior wall lead in inferior myocardial infarction were studied in coronary angiographic findings in the acute stage. The subjects were 40 patients with initial inferior myocardial infarction due to right coronary lesions. ST segments were elevated in 7 patients, remained unchanged in 11 and were depressed in 22. Two patients predominantly perfused in the left coronary artery showed ST elevation. All seven patients who showed elevation of the ST segments had occlusion of the ventricular branch proximal to right. However, another 15 (68%) of the patients with occlusion of the same lesion did not show elevation of any ST segment. There was no difference in left ventricular ejection fraction between the groups. The regional ejection fraction at the left ventricular inferior wall was significantly (p less than 0.01) higher in the ST elevated group than in the ST depressed group. Elevation of the ST segments in the anterior wall lead was observed only when the right ventricular free wall sustained injury, and no elevation of any ST segment was observed when the range of injury in the inferoposterior wall was wide, even in the presence of injury to the right ventricular free wall.     

Right ventricular infarction mimicking anterior infarction: A case report

Right ventricular infarction usually occurs in association with inferior infarction, with no remarkable electrocardiographic signs in conventional leads. This report describes a patient with a previous inferior acute myocardial infarction who developed right ventricular infarction with significant anterior lead ST segment elevation (V1-V4) caused by the loss of two large right ventricular branches during a coronary angioplasty of the right coronary artery. The case is discussed and the literature is reviewed.     

Primary angioplasty for isolated right ventricular infarction.

We describe a case of isolated right ventricular infarction that has rarely been diagnosed antemortem. Electrocardiogram showed ST segment elevation in left precordial chest, right precordial chest, and inferior leads, which mimicked those of anterior and inferior left ventricular infarction. Coronary angiography revealed that culprit lesion was totally occluded right coronary artery. Infarcted artery was nondominant right coronary artery with branches supplying only right ventricular wall. Restoration of coronary blood flow was obtained by primary stenting and resulted in prompt ST segment normalization in all leads. Despite extensive right ventricular wall motion abnormality, subsequent right ventricular dysfunction was not observed.     

Pure right ventricular infarction.

A 76-year-old man with chest pain was admitted to hospital where electrocardiography (ECG) showed ST-segment elevation in leads V1-4, indicative of acute anterior myocardial infarction. ST-segment elevation was also present in the right precordial leads V4R-6R. Emergency coronary angiography revealed that the left coronary artery was dominant and did not have significant stenosis. Aortography showed ostial occlusion of the right coronary artery (RCA). Left ventriculography showed normal function and right ventriculography showed a dilated right ventricle and severe hypokinesis of the right ventricular free wall. Conservative treatment was selected because the patient's symptoms soon ameliorated and his hemodynamics was stable. 99mTc-pyrophosphate and 201Tl dual single-photon emission computed tomography showed uptake of 99mTc-pyrophosphate in only the right ventricular free wall, but no uptake of 99mTc-pyrophosphate and no perfusion defect of 201Tl in the left ventricle. The peak creatine kinase (CK) and CK-MB were 1,381 IU/L and 127 IU/L, respectively. His natural course was favorable and the chest pain disappeared under medication. Two months after the onset, the ECG showed poor R progression in leads V1-4 indicating an old anterior infarction. Coronary angiography confirmed the ostial stenosis of the hypoplastic RCA. This was a case of pure right ventricular free wall infarction because of the occlusion of the ostium of the hypoplastic RCA, but not of the right ventricular branch. Because the electrocardiographic findings resemble those of an acute anterior infarction, it is important to consider pure right ventricular infarction in the differential diagnosis.     

ST segment elevation in anterior precordial leads and right ventricular infarction. Apropos of 6 cases]

ST segment elevation in the anterior precordial chest leads may be observed in some cases of right ventricular infarction alone or associated with left ventricular inferior wall infarction. Six out of 700 patients admitted to our Coronary Care Unit over a 2 year period had right ventricular infarction with these electrocardiographic changes. In three cases, isolated right ventricular infarction was due to occlusion of a right marginal artery (N = 2) or of a small right coronary artery (N = 1) which only vascularised the right ventricle. In 2 cases, right ventricular infarction was associated with a recent or chronic left ventricular inferior wall infarct. This type of ST segment elevation may suggest a left ventricular anterior wall infarct especially when there are no changes in the inferior leads, as was the case in our first patient. However, the dome-like appearance of the ST segment, the reduction in amplitude of ST elevation from V2 to V5, the progressive regression of the ST changes without the appearance of Q waves, are more suggestive of the diagnosis of right ventricular infarction. In addition, normal left ventricular dilatation on echocardiographic examination rapidly confirms the diagnosis.     

Right ventricular infarction: frequency, size and topography in coronary heart disease: a prospective study comprising 107 consecutive autopsies from a coronary care unit

During a 14 month period autopsies were performed on 107 patients with coronary heart disease and the results were evaluated prospectively with special reference to right ventricular infarction. A total of 214 regional infarcts were found, 107 (50%) of which involved the right ventricle. Right ventricular infarction was found in 90 hearts (84%), but only three isolated right ventricular infarcts were seen. Right ventricular involvement was found with equal frequency in anterior and posterior infarction (64 versus 66%), but posterior right ventricular infarcts were much larger (15% of the right ventricle was infarcted versus 1%). Proximal right coronary artery occlusion caused larger right ventricular infarction than did distal occlusion (15 versus 5 g). Right ventricular infarct size was not influenced by coronary artery disease (evaluated angiographically) in noninfarct-related vessels. Anterior right ventricular infarcts were predominantly located near the apex of the heart (to the left of the sternum), whereas posterior right ventricular infarcts were located near the atrioventricular groove (along the right sternal border). Infarct size was equal in patients who died from a first acute anterior or posterior infarct. However, posterior infarcts had more right ventricular involvement (28% of total infarct size versus 7% in anterior infarcts) leaving more of the left ventricular myocardium intact (79 versus 64%). These differences in infarct topography may explain why right ventricular involvement seldom is diagnosed clinically in patients with anterior infarction, and why left ventricular function and prognosis usually are better after posterior compared with anterior infarcts of enzymatically equal size.     

Electrocardiographic, arteriographic and ventriculographic correlations in transmural myocardial infarction

To determine if significant interrelations exist between the electrocardiographic diagnosis of transmural myocardial infarction, sites of coronary arterial obstruction, and left ventricular asynergy, 235 patients with angiographically documented coronary artery disease were subdivided according to the electrocardiographic location of the myocardial infarction, the coronary arterial system involved and the site of ventricular asynergy. Of 82 instances of anterior myocardial infarction, the left anterior descending artery demonstrated significant disease in 79 (96 percent). Of 100 instances of inferior myocardial infarction, the right coronary artery was significantly diseased in 87 and the left circumflex in 55. When multiple infarctions were present, multivessel disease was found in 93 percent of patients. Left ventricular asynergy was present in 81 percent, including 84 percent of those with anterior infarction, 74 percent of those with inferior infarction, and 93 percent of those with multiple infarctions. The results of our study suggest that the electrocardiogram is often of value in indicating sites of coronary arterial obstruction and ventricular asynergy in patients with coronary artery disease and transmural myocardial infarction.     

Combined right and left ventricular infarction: Pathogenesis and clinicopathologic correlations

An autopsy examination was made in 102 consecutive cases of fatal myocardial infarction that occurred in a coronary care unit. Thirty-five of the patients (34 percent) were found to have right ventricular infarction. All of the right ventricular infarcts were associated with transmural infarction of the posterior left ventricle or the interventricular septum, or both. The group with right ventricular infarction was compared with that without right ventricular infarction. Both groups had a predominant pattern of coronary arterial atherosclerosis consisting of severe stenosis of the proximal left anterior descending and proximal right coronary arteries with variable involvement of the left circumflex and left main coronary arteries. There was no significant difference between the two groups in severity or distribution of coronary arterial atherosclerosis. However, the group with right ventricular infarction had twice as many recent coronary arterial occlusions as did the group with left ventricular infarction and at least one recent coronary arterial lesion was present in 86 percent of those with right ventricular infarction, compared with only 30 percent of the group with left ventricular infarction. The majority of the acute coronary arterial lesions in both groups were thrombotic, but many intramural hemorrhages within atherosclerotic plaques were also found. In both groups the greatest number of recent coronary arterial occlusions was in the proximal right coronary artery, but the acute lesions were distributed throughout the coronary arterial tree.     

Nonfatal myocardial infarction in medically treated patients with coronary artery disease

The purpose of this study was to identify patient characteristics associated with nonfatal myocardial infarction as the first event after cardiac catheterization in medically treated patients with coronary artery disease. Multiple logistic risk analyste of 81 baseline characteristics in 354 patients who died or had nonfatal infarction identified 10 characteristics (5 clinical and 5 cardiac catheterization variables) as independently discriminating between the two events. Left ventricular function, specific coronary anatomy, previous myocardial infarction and age were the most important discriminators. Poor left ventricular function and left main coronary stenosis were associated with death. Subtotal left anterior descending and right coronary arterial stenosis, normal hemodynamics, absence of previous infarction and young age were associated with nonfatal infarction. Thus, in any subset of patients who have a uniform risk of ischemic events (nonfatal infarction or death), nonfatal infarction is most likely to occur in those who are young, have had no previous infarction, have subtotal left anterior descending and right coronary arterial stenosis and normal hemodynamics.     

Acute right ventricular infarction without infero-posterior left ventricular infarction

Two cases of acute right ventricular infarction associated with acute extensive anterior myocardial infarction in the absence of inferior and/or posterior left ventricular infarction are presented. Such a combination is likely to occur from acute occlusion of the left anterior descending artery in the face of severe narrowing of the infundibular (conus) artery rather than from acute occlusion of the right coronary artery.     

Global and regional right ventricular function after acute myocardial infarction: dependence upon site of left ventricular infarction

The relation of global and regional right and left ventricular function during the acute phase after a first myocardial infarction was assessed by first pass radionuclide angiography in 20 patients (10 after anterior and 10 after inferior myocardial infarction). The right ventricular ejection fraction did not differ significantly between the groups, but left ventricular ejection fraction was significantly depressed after anterior myocardial infarction. There was evidence of right ventricular dilatation and impaired transit in the group with inferior infarction. Five patients with anterior infarction and six with inferior infarction had abnormal right ventricular ejection fractions. Right ventricular wall motion abnormalities affected the septal wall in the group with anterior infarction and the free wall in the group with inferior infarction. The relation between right and left ventricular ejection fractions was markedly different in the two groups. In the group with anterior infarction there was a significant linear relation between right and left ventricular ejection fraction, whereas in the group with inferior infarction there was not. Thus right ventricular dysfunction commonly occurs after both anterior and inferior myocardial infarction. Right and left ventricular impairment are related after anterior myocardial infarction, but are independent after inferior myocardial infarction. Finally, the different effects of anterior and inferior myocardial infarction on right ventricular function may be explained by differences in septal and free wall involvement.     

急性下壁心肌梗死患者血B型利钠肽的研究

目的:探讨急性下壁心肌梗死(AIMI)患者伴或不伴有右心肌梗死与血浆B型利钠肽(BNP)水平的相关性.方法:入选AIMI患者213例,依据临床表现、心电图和冠状动脉造影将213例AIMI患者分为伴有右心室梗死组(A组) 和单纯AIMI组(B组),另选同时期住院冠状动脉造影正常者98例作正常对照组.测定各组及AIMI中不同病变部位者BNP水平,并对不同BNP水平患者进行住院期间、30 d、3个月死亡事件及主要心脏不良事件的临床观察.结果:A组血浆BNP水平明显高于B组(P<0.01).右冠状动脉近段和中段病变患者血浆BNP水平显著高于左回旋支病变患者(P<0.01).AIMI患者中血浆BNP水平升高独立于各因素预测30 d和3个月病死率及心脏不良事件发生率(r=0.701 0, 95% CI:<0.01～0.615, P<0.01).结论:BNP水平可能对AIMI伴右心室梗死有预测作用.     

Global and regional right ventricular function after acute myocardial infarction: dependence upon site of left ventricular infarction.

The relation of global and regional right and left ventricular function during the acute phase after a first myocardial infarction was assessed by first pass radionuclide angiography in 20 patients (10 after anterior and 10 after inferior myocardial infarction). The right ventricular ejection fraction did not differ significantly between the groups, but left ventricular ejection fraction was significantly depressed after anterior myocardial infarction. There was evidence of right ventricular dilatation and impaired transit in the group with inferior infarction. Five patients with anterior infarction and six with inferior infarction had abnormal right ventricular ejection fractions. Right ventricular wall motion abnormalities affected the septal wall in the group with anterior infarction and the free wall in the group with inferior infarction. The relation between right and left ventricular ejection fractions was markedly different in the two groups. In the group with anterior infarction there was a significant linear relation between right and left ventricular ejection fraction, whereas in the group with inferior infarction there was not. Thus right ventricular dysfunction commonly occurs after both anterior and inferior myocardial infarction. Right and left ventricular impairment are related after anterior myocardial infarction, but are independent after inferior myocardial infarction. Finally, the different effects of anterior and inferior myocardial infarction on right ventricular function may be explained by differences in septal and free wall involvement.     

Right ventricular infarction complicating left ventricular infarction secondary to coronary heart disease: Frequency, location, associated findings and significance from analysis of 236 necropsy patients with acute or healed myocardial infarction

Right ventricular infarction associated with left ventricular infarction was identified by gross examination at necropsy in 33 (14 percent) of 236 patients with transmural myocardial infarction. Right ventricular infarction occurred exclusively as a complication of posterior left ventricular infarction. Associated right ventricular infarction occurred in none of the 97 patients with isolated anterior wall infarction of the left ventricle, but in 33 (24 percent) of the 139 patients with posterior left ventricular infarction. Transmural infarction of the posterior ventricular septum was an additional prerequisite for right ventricular infarction. Of the 139 patients with infarction of the posterior left ventricular wall, 74 had no transmural infarction of the ventricular septum and none of these 74 had associated right ventricular infarction. In contrast, of the 65 patients with infarction of the posterior left ventricular wall and transmural infarction of the ventricular septum, 33 (50 percent) had associated right ventricular infarction.

Among the 33 patients with right ventricular infarction, the infarct was limited to the posterior right ventricular free wall in 27 (82 percent); in the other 6 patients (18 percent) it extended to involve the anterolateral right ventricular free wall. Among patients with a posterior left ventricular infarct, those with a right ventricular infarct had right ventricular dilatation nearly three times (P < 0.05) more frequently than the patients without a right ventricular infarct. Comparison of the same two groups disclosed no differences in the patients' age, sex, extent of coronary arterial luminal narrowing, right ventricular hypertrophy, right ventricular thrombi or duration of symptoms of myocardial ischemia.

Hemodynamic data in four patients with a right ventricular infarct disclosed previously reported characteristic hemodynamics of right ventricular infarction in only one patient. Recognition of right ventricular infarction is important because it implies specific therapy, namely, aggressive volume administration. Clinical evidence of posterior left ventricular infarction and right ventricular dilatation should arouse strong suspicion of associated right ventricular infarction.     

Right ventricular myocardial infarction with anterior wall left ventricular infarction: an autopsy study

Right ventricular myocardial infarction has been reported to occur exclusively in association with inferior left ventricular infarction. To determine the frequency of right ventricular myocardial infarction in association with anterior left ventricular myocardial infarction, all hearts with anterior myocardial infarction studied over a 3-year period were examined for evidence of right ventricular necrosis or scar. Of 97 hearts with anterior myocardial infarction, 13 (13%) had anterior right ventricular myocardial infarction. The right ventricular infarcts involved from 10% to 50% (mean 28%) of the circumference of the right ventricular free wall from base to apex. The associated left ventricular infarcts were all anteroseptal and large and involved from 36% to 67% (mean 50%) of the total area of the left ventricular free wall and septum. Nine of the 13 patients underwent equilibrium radionuclide angiography and six had demonstrable right ventricular regional and global dysfunction. Thus, right ventricular myocardial infarction does occur with anterior wall left ventricular infarction, and right ventricular dysfunction may be demonstrable by radionuclide angiography. Further investigation is needed to define the hemodynamic characteristics, clinical importance, and therapeutic implications of anterior right ventricular myocardial infarction.     

Quantitative analysis of right and left ventricular infarction in the presence of postinfarction ventricular septal defect

To quantitate the amount of right and left ventricular infarction in patients dying with postinfarction ventricular septal defect (PIVSD), hearts from 54 patients with anterior or inferior myocardial infarction were studied at autopsy. Fifteen hearts had myocardial infarction with PIVSD and 39 hearts had infarction without PIVSD and were used as a comparison group. All infarcts were sized histologically and the percent of each ventricle infarcted was quantitated by computer-assisted planimetry. The pathologic substrate for PIVSD was diffuse coronary artery disease with acute thrombosis resulting in transmural confluent infarction. Within the PIVSD group, there was significantly more left ventricle involved in anterior infarctions than in inferior infarctions (p less than .04). Conversely, there was more right ventricular infarction in inferiorly located myocardial infarctions with resulting PIVSD (p = .059). When infarctions resulting in PIVSD were compared with infarctions not resulting in PIVSD, the PIVSD group was characterized by larger left and right ventricular infarcts irrespective of infarct location (p less than .003). The incidence of right ventricular infarction was 100% in the PIVSD group (p less than .0001). Twelve of the 15 patients with PIVSD (80%) developed cardiogenic shock within 48 hr of septal rupture. The high incidence of shock and the rapid deterioration may have been secondary to right ventricular infarction in these patients. Therefore, infarcts resulting in PIVSD and subsequent death are characterized by a high incidence of right ventricular infarction. Significantly more infarction of the right ventricle is seen in either anterior or inferior infarctions resulting in PIVSD compared with infarctions not resulting in PIVSD. PIVSD complicating inferior infarctions is associated with the greatest amount of right ventricular infarction.     

Coronary collaterals and left ventricular function early after acute transmural myocardial infarction

The coronary collateral circulation and ventricular function,segmental wall motion and infarct size, were investigated fromhemodynamic and angiographic data in 126 patients with acutetransmural myocardial infarction and complete obstruction ofa major coronary vessel. The patients were divided into twogroups: 74 with obstruction of the right coronary artery and52 with obstruction of the left anterior descending artery.The collateral circulation was rated as absent, poor, fair oradequate: two weeks after infarction, collateral vessels wereobserved in only 27% (poor 15.4%, fair 5.8%, adequate 5.8%)of the patients with an anterior myocardial infarction and inonly 35% (poor 13.5%, fair 16.4%, adequate 4.5%) of the patientswith an inferior myocardial infarction. In both groups of patients, the presence of collateral vesselshad no significant influence on the following parameters: leftventricular performance (left ventricular end-diastolic pressure,left ventricular enddiastolic volume, ejection fraction andmean velocity of fiber shortening), extent of abnormally contractingsegment and segmental wall motion. After anterior myocardialinfarction, there was an insignificant trend to lesser myocardialdamage in patients with coronary collaterals. Thus, coronary collaterals are infrequent in patients with acutetransmural myocardial infarction and total obstruction of acoronary vessel; in these patients we conclude that the collateralshave no effect either on left ventricular function or on thesize of the infarction.