Coronary angiography and left ventriculography in survivors of transmural and nontransmural myocardial infarction

Recent studies have suggested a similar prognosis for patients with transmural myocardial infarction and nontransmural myocardial infarction despite a smaller infarct size in the latter patients estimated by creatine phosphokinase (CPK). Thirty-one patients with transmural myocardial infarction and 17 patients with nontransmural myocardial infarction as defined by electrocardiographic criteria underwent coronary angiography and left ventriculography from 10 to 24 days after they had an acute myocardial infarction. Forty-three of these 48 patients were asymptomatic following their myocardial infarction. When compared to patients with nontransmural myocardial infarction, those with transmural myocardial infarction had greater peak CPK levels, 1,090 +/- 210 versus 290 +/- 60 IU (p less than 0.01). There was no difference in prevalence of single, double or triple vessel coronary artery disease, mean number of coronary arteries 50 per cent narrowed (2.0 +/- 0.2 versus 2.0 +/- 0.2), near total or total occlusions, coronary score (Friesinger) (7.9 +/- 0.6 versus 8.2 +/- 0.7), left ventricular ejection fraction (48 +/- 2 versus 53 +/- 4), or per cent of akinetic-dyskinetic myocardial segments (66 of 242 [27 per cent] versus 32 of 132 [24 per cent]) between two groups. The similar extent of coronary artery narrowing and degree of left ventricular dysfunction may explain the similar prognosis for patients with transmural myocardial infarction and those with nontransmural myocardial infarction despite differences in enzymatically estimated acute infarct size.     

Nontransmural myocardial infarction: A comparison of hospital and late clinical course of patients with that of matched patients with transmural anterior and transmural inferior myocardial infarction

The hospital and long-term course of 67 patients with nontransmural myocardial infarction was compared with that of 66 patients with transmural anterior and 63 patients with transmural inferior infarction matched for age, sex, previous infarction and prior congestive heart failure. During their hospital stay, patients with nontransmural infarction had significantly less congestive heart failure and fewer intraventricular conduction defects than did patients with transmural anterior infarction; fewer atrial tachyarrhythmias and less sinus bradycardia and atrioventricular block than did patients with transmural inferior infarction; and an incidence of hypotension, pericarditis and ventricular irritability similar to that of patients in the other two groups. Patients with nontransmural infarction had a significantly lower coronary care unit mortality rate (9 percent) than that of patients with transmural anterior or transmural inferior infarction (20 and 19 percent, respectively). By 3 months, the mortality rate had risen to 14 percent in patients with nontransmural infarction, but was significantly higher (29 and 27 percent, respectively) in patients with transmural anterior or transmural inferior infarction. Angina was common in all three groups, occurring in more than 50 percent of patients during a mean follow-up period of 28.6 months after hospital discharge.In contrast, the incidence of subsequent myocardial infarction was significantly greater in patients with nontransmural myocardial infarction, occurring in 21 percent at 9 months compared with only 3 percent of patients with transmural anterior (p <0.01) and 2 percent of patients with transmural inferior (p <0.05) infarction. By 54 months, 57 percent of patients with nontransmural infarction had sustained a new infarction contrasted with only 12 percent of patients with transmural anterior (/p <0.001) and 22 percent of patients with transmural inferior (p <0.01) infarction. Late mortality increased in patients with nontransmural myocardial infarction and, although this group had a significantly better survival rate at 3 months, the overall late mortality of the three groups was comparable. The study suggests that nontransmural myocardial infarction is an unstable ischemic event associated with a great risk of later myocardial infarction and high late mortality rate. A more aggressive diagnostic and therapeutic approach may be warranted in patients with nontransmural myocardial infarction.     

Survival of patients with nontransmural myocardial infarction: A population-based study

A population-based study was conducted in metropolitan Baltimore in which the short- and long-term prognosis of 283 patients with nontransmural myocardial infarction was compared with that of 953 patients with transmural infarction. After simultaneous adjustment for several variables, the in-hospital case fatality rate was greater for patients with transmural (30.1 percent) than with nontransmural (18.3 percent) infarction (P < 0.01). However, for patients discharged alive from the hospital and followed up for as long as 10 years, no significant differences in survival were found between the groups with transmural and nontransmural infarction. A multiple adjustment procedure yielded 3 year case fatality rates of 27.1 percent and 28.3 percent, respectively, for patients with transmural and nontransmural myocardial infarction surviving the acute phase.These results suggest that the long-term prognosis of patients with nontransmural infarction is as guarded as that of patients with transmural infarction and that attempts to prevent subsequent mortality should be diligently pursued in both groups of patients.     

Nontransmural versus transmural myocardial infarction: A morphologic study

Although “nontransmural” and “transmural” are morphologic terms used widely to distinguish patients with myocardial infarction, controversy exists as to their meaning regarding clinical course. For this study, a transmural infarct was defined as one that involves essentially the full thickness of the ventricular wall, and nontransmural was defined as something less. The purpose of this study was to identify true morphologic nontransmural acute (less than 21 days old) infarcts at autopsy and compare them with transmural (full-thickness) infarcts in age-matched subjects, for clinical and pathologic similarities and differences. Among the autopsy subjects, comparing 35 nontransmural and 35 transmural infarcts, there was no significant difference with regard to subjects' race or sex, chest pain, arrhythmias, heart block, or cause of death; transmural myocardial infarctions did have a higher frequency of new Q waves (30 of 35 versus six of 35, p < 0.001) and presented more often with increasing dyspnea. At autopsy, there were no significant differences regarding heart weight, location of infarcts, severity of coronary disease, age of acute infarct, or total size of infarct (18 percent of left ventricle for nontransmural versus 22 percent for transmural). There was, however, a significantly greater tendency for those with nontransmural infarct to have evidence of prior infarction at autopsy (27 of 35 versus 19 of 35, p < 0.05). Acute coronary thrombi in the distribution of the infarct were significantly more common among transmural myocardial infarcts (32 of 35 versus 18 of 35, p < 0.001). Morphologically, the nontransmural infarcts showed mural involvement ranging from 20 to 90 percent of the left ventricle, and histologically showed more contraction band (i.e., reflow) injury (57 percent with more than 30 percent contraction band necrosis) compared with transmural infarcts (32 percent with more than 30 percent contraction band necrosis) (p < 0.05). Fatal nontransmural and transmural infarcts have major clinical and pathologic similarities, but differences in number of prior infarcts, type of necrosis, and occurrence of coronary thrombi suggest differing pathophysiology. The heterogeneity of both transmural and nontransmural infarcts likely accounts for existing differences among clinical studies regarding prognosis. Although this classification system has value in the clinical setting, that at times it represents an imprecise oversimplification of infarct type should be recognized in assessing individual patients.     

A Comparison of Nontransmural and Transmural MyocardiaI Infarction

Summary: A comparison of nontransmural and transmural myocardial infarction. J. Boxall and A. Saltups, Aust. N.Z. J. Med ., 1 980, 10 , pp. 176–179.
This report compares the past history, hospital course and follow-up of 70 patients with nontransmural myocardial infarction compared to 259 patients with transmural myocardial infarction
The pre-infarction history in the two groups is similar with respect to angina and infarction. The hospital course for non-transmural myocardial infarction is not a guide for future cardiac events and the post-hospital prognosis in the two groups is similar. Nontransmural myocardial infarction has a lower hospital mortality ( P <0.05). Patients in whom nontransmural myocardial infarction is a first coronary event have a lower incidence of subsequent angina ( P < 0.05).
The study demonstrates that myocardial infarction without development of q waves does not have an unfavourable long term outlook when compared to transmural infarction. This finding is contrary to reports which suggest a poor prognosis and recommend early coronary anteriography with a view to aorto-coronary bypass in patients with nontransmural infarction     

Clinical characteristics,electrocardiographic and enzyme correlations,and long-term prognosis of patients with chest pain associated with ST depression and/or T wave inversion

The clinical characteristics, electrocardiographic changes, and long-term prognosis were studied in 50 patients suffering nontransmural myocardial infarctions. It is concluded that nontransmural myocardial infarcts tend to occur in older patients with known coronary atherosclerosis and these infarctions are frequently preceded by a period of unstable angina. The clinical course is often complicated with congestive heart failure and other major management problems. Three different groups of electrocardiographic changes were noted and all four in-hospital deaths showed the same pattern of electrocardiographic changes. The prognosis of patients suffering nontransmural myocardial infarctions is not good, as evidenced by a death rate similar to reported patients suffering transmural myocardial infarction and a significant incidence of cardiovascular disability in those who survive.     

Left ventricular functional alterations at rest and during submaximal exercise in patients with recent myocardial infarction

Submaximal exercise testing with radionuclide ventriculography was performed in 117 patients prior to hospital discharge 16.7 ± 6.7 days (SD) following acute myocardial infarction. The hypothesis tested in this study was that patients with different locations and types of infarction have different functional responses to submaximal exercise prior to discharge. The distribution of the myocardial infarctions were anterior transmural in 33, Inferior transmural in 39, anterior nontransmural in 23, inferior nontransmural in 19, and indeterminant in three. Patients with transmural infarction generally had significantly larger resting left ventricular volumes at enddiastole and end-systole and lower ejection fractions and systolic blood pressure/end-systolic volume Indexes than patients with nontransmural infarctions (p < 0.05). During submaximal exercise, the change in end-systolic volume was significantly different in these two groups. When patients were separated further into anterior and inferior transmural subgroups, the patients with anterior transmural infarction had significantly lower left ventricular ejection fractions and higher right ventricular ejection fractions than the group with inferior transmural Infarction (p < 0.05). In response to exercise, the group with anterior transmural infarction had a significant decrease in left ventricular ejection fraction and a blunted systolic blood pressure/left ventricular end-systolic volume index, in comparison to patients with inferior myocardial infarction (p < 0.05); this was the only group to have a significant increase in end-systolic volume. The group variance for the parameters studied was large, particularly during exercise when the individual responses were frequently directionally opposite from the group means. The group with anterior transmural infarction was the most homogenous, with 26 of 33 having a directionally abnormal response to submaximal exercise. It was concluded that the group with anterior transmural infarction generally displayed the most abnormal left ventricular function. However, despite significant group differences in resting ventricular function with different infarcts, the intragroup variability at rest and in response to exercise was too great to permit an accurate prediction of the subject's resting ventricular performance or to permit a prediction of exercise response based solely on location of the infarct.     

Nondiagnostic electrocardiogram in patients with acute myocardial infarction. Clinical and anatomic correlations

The electrocardiograms of 78 of 230 patients with acute myocardial infarction showed only nondiagnostic changes in the S-T segment and T waves. On the basis of serum enzyme curves, two groups were defined: group A, 45 patients with definite myocardial infarction and group B, 33 patients with probable myocardial infarction. Three subgroups emerged in each group: group I, 38 patients with significant S-T segment depression with or without T wave changes; group II, 34 patients with significant T waves changes only; and group III, 6 patients with significant S-T segment elevation with or without T wave changes. The incidence of sinus tachycardia was significantly greater in group AI (13 patients or 48 per cent) (p <0.05) than in groups AII, AIII, BI, BII and BIII, but that of other arrhythmias was similar in all. The incidence of shock in group AI (eight patients or 30 per cent) was significantly greater than in groups AII, AIII, BI, BII and BIII (p <0.1). Mortality was also greater in group AI (13 patients or 47 per cent) (p <0.05) than in groups AII, AIII, BI, BII and BIII. There was no significant difference in the incidence of arrhythmias, shock or mortality among groups BI, BII and BIII. Postmortem examination of 8 of 18 patients (44 per cent) revealed recent transmural myocardial infarction with associated prior infarction in all.We have identified a subgroup of patients (group AI) with acute myocardial infarction and nondiagnostic electrocardiograms who appear to be at a greater risk of dying. The electrocardiographic changes correlated poorly with major clinical manifestations, as well as the magnitude or geographic location of the myocardial infarction. For all patients with acute myocardial infarction and nondiagnostic electrocardiograms, the ultimate prognosis appears to be determined by the extent of recent infarction, as reflected in the enzyme rise, as well as the magnitude of prior myocardial necrosis.     

Prevalence and prognosis after a first nontransmural myocardial infarction

Prevalence, prognosis, and coronary anatomy associated with nontransmural myocardial infarction (MI) were prospectively assessed in 458 consecutive men admitted to our coronary care unit with a first MI. Cardiac catheterization was performed in 402 of the 436 survivors within 1 month of the acute event. Mean follow-up was 33 months (range 5 to 72). Nontransmural MI was diagnosed in 28 patients (6%). These patients were younger (46 ± 10 versus 51 ± 7 years, p < 0.001) and had lower peak creatine kinase values (601 ± 319 versus 1,141 ± 923 U, p < 0.01) and better ejection fraction (63 ± 8 versus 46 ± 14, p < 0.001) than did their counterparts. Survivors of nontransmural MI also had fewer affected arteries (p < 0.001) and a lower prevalence of total or subtotal occlusion (> 90%) in the involved artery (p < 0.01). Mortality in the acute phase and long-term survival at 4 years (Kaplan-Meier) in patients with nontransmural MI (94%) were similar to those in patients with transmural MI (90%). The occurrence of new nonfatal coronary events was also similar in both groups of MI survivors. Thus, in the absence of symptoms, more aggressive management to improve survival does not seem warranted after nontransmural MI.     

Increased incidence and clinical correlation of persistently abnormal technetium pyrophosphate myocardial scintigrams following acute myocardial infarction in patients with diabetes mellitus

"Persistently abnormal" technetium-99m stannous pyrophosphate myocardial scintigrams (PPi+) appear to be associated with a relatively poor prognosis after acute myocardial infarction (AMI). To assess the incidence and implications of PPi+, we performed a retrospective analysis in 29 patients with and 25 patients without diabetes mellitus who had abnormal myocardial scintigrams within 4 days of AMI and who had follow-up scintigrams at least 3 months after hospital discharge. There were no significant differences between patients with and without diabetes as regards age, incidence of transmural or nontransmural AMI, or degree of left ventricular dysfunction after AMI. Persistently abnormal PPi+ occurred more commonly in patients with diabetes than in nondiabetic patients (18 of 29, 62%, compared to 3 of 25, 12%; p less than 0.001). Patients with chronic PPi+ had more frequent cardiac complications following hospital discharge (p less than 0.005) including death, recurrent AMI, unstable angina, and intractable congestive heart failure. Postmortem analysis in two patients with diabetes and chronic PPi+ revealed marked myocytolysis. Thus, patients with diabetes mellitus have an increased incidence of post-AMI "persistently abnormal" technetium (PPi+) scintigrams and relatively poor prognosis following myocardial infarction.     

The clinical course, early prognosis and coronary anatomy of subendocardial infarction.

The following prospective study was undertaken to observe the clinical course, early prognosis and coronary anatomy of patients with subendocardial infarction. Subendocardial infarction was defined as typical chest apin (greater than 15 minutes), serum enzyme elevation and persistent (greater than 48 hours) new T wave inversion and/or S-T segment depression in the absence of new pathologic Q waves. Fifty consecutive patients were defined, followed in a prospective manner and subjected to early coronary arteriography. A prior history of unstable angina was found in 33 patients (66 per cent); 22 patients (44 per cent) had significant dysrhythmias during the acute hospital phase, and seven patients (14 per cent) had evidence of mild left ventricular failure. Coronary arteriography demonstrated significant lesions (greater than 75 per cent narrowing in at least one vessel) in all 50 patients, with 30 patients (60 per cent) having either double- or triple-vessel disease. Follow-up (mean 10.6 months) revealed that 15 patients (30 per cent) had stable angina, 23 patients (46 per cent) unstable angina and only 12 patients (24 per cent) remained free of angina. Of 28 patients in a medically treated group, acute transmural infarctions developed in six (21 per cent) and one died (3 per cent). We conclude that subendocardial infarction is symptomatically an unstable entity, is associated with severe coronary artery disease and, in a medically treated group, is followed by a significant incidence of early transmural myocardial infarction (21 per cent). Therefore, these patients require in-hospital monitoring, careful follow-up and consideration for early coronary arteriography.     

Subendocardial and transmural myocardial infarction: a five year survival study.

Two hundred seventy-six patients (median age 66 years) were discharged from the hospital following an acute myocardial infarction. Based on their electrocardiograms, they were divided into the following three groups: group 1, 127 patients with transmural infarction, i.e., with Q-wave development; group 2, 98 patients with subendocardial infarction, i.e., with S-T segment changes but without Q-wave development; and group 3, 51 patients with nondiagnostic electrocardiograms but with typical symptoms and enzymatic changes. The five year survival rates were not statistically significantly different (59 per cent, group 1; 51 per cent, group 2; and 41 per cent, group 3). Within the three groups, we found a statistically significant lower survival for (1) patients who were above 65 years of age, (2) patients who had a preadmission history of cardiovascular disease, (3) patients who had heart failure and arrhythmias during treatment in the hospital; and (4) patients who needed medical treatment on discharge. Thirteen per cent of the patients in the latter two catagories died suddenly within the first year. Thirty-three per cent of the patients with all these factors survived five years compared to 83 per cent of the patients with none of these factors. The electrocardiographic changes suggesting transmural or subendocardial infarction were not associated with differences in the long-time prognosis.     

Thallium-201 versus technetium-99m pyrophosphate myocardial imaging in detection and evaluation of patients with acute myocardial infarction

Thallium-201 myocardial imaging is of value in the early detection and evaluation of patients with suspected acute infarction. The extent of a thallium defect in an initial myocardial image may have important prognostic value. Tomographic imaging techniques hold promise for increased diagnostic sensitivity and more accurate quantitation of both infarcted and residual viable myocardium. Thallium imaging may have a special value in characterizing patients with cardiogenic shock and in detecting patients at risk for subsequent infarction or death or both, before hospital discharge.

Approximately 95 percent of patients with transmural or nontransmural myocardial infarction can be detected with technetium-99m pyrophos-phate myocardial imaging if the imaging is performed 24 to 72 hours after the onset of symptoms. Pyrophosphate imaging has been useful in localizing the site and determining the extent of acute myocardial infarction. The “doughnut” pattern is associated with a relatively large incidence of subsequent congestive heart failure and death. However, the clinical utility of this information is limited because it is usually not available when it is most needed, on admission to the coronary care unit. Pyrophosphate imaging may have an important role in the evaluation of patients during the early follow-up period after hospital discharge from an episode of acute infarction. The finding of a persistently positive pyrophosphate image suggests a poor prognosis and is associated with a relatively large incidence of subsequent myocardial infarction and death.     

Quantitative comparison of extent of coronary narrowing and size of healed myocardial infarct in 33 necropsy patients with clinically recognized and in 28 with clinically unrecognized (“silent”) previous acute myocardial infarction

Clinical and necropsy observations are described in 61 patients with a healed transmural myocardial infarction, 33 with and 28 without a clinical history of acute myocardial infarction. There were no significant differences between the 2 groups of patients in mean age, sex, or frequency of angina pectoris, chronic congestive heart failure, systemic hypertension, sudden coronary death, or fatal acute myocardial infarction. Compared with the patients with clinically recognized acute myocardial infarction, the patients with clinically unrecognized (silent) infarction had a significantly (p < 0.05) higher incidence of diabetes mellitus (43 versus 15%), death from noncardiac causes (39 versus 9%), posterior (inferior) wall infarcts (82 versus 55%), and smaller infarcts (mean size 7 versus 17% of left ventricular wall). The patients with and without clinically recognized infarction had similar numbers of the 4 major coronary arteries severely (76 to 100% in cross-sectional area) narrowed (mean 2.8 versus $\text{2.9}\text{4.0}$ per patient), insignificant differences in incidence of severe narrowing of the left main coronary artery (18 versus 29%), similar overall percents of 5 mm segments of the 4 major coronary arteries severely narrowed (43 versus 42%), and similar percents of severely narrowed 5 mm segments of the right (46 versus 55%), left anterior descending (39 versus 33%), and left circumflex (41 versus 41%) coronary arteries.     

Five-year survival of 728 patients after myocardial infarction. A community study.

This study deals with the five-year survival of 728 myocardial infarction patients who survived the first 28 days after the onset of symptoms. The series was collected by the Helsinki Coronary Register and includes all cases of acute myocardial infarction in the population who were under 66 years of age during the period 1 July 1970 to 30 June 1971. Of the 219 patients who subsequently died, 81.8 per cent died from ischaemic heart disease. The mortality was highest during the first year after the acute phase but did not decrease after the second year. The mortality was higher in patients with a transmural infarction (five-year mortality 34.0%) compared with those with a nontransmural infarction (19.7%). The mortality also was higher for recurrent acute myocardial infractions than for first attacks. The five-year mortality for women was less (20.5%, age-adjusted) than for men (31.6%). This is mainly because of the higher incidence of nontransmural infarcts in women. Acute ischaemic heart disease is more common, more often fatal, and has a poorer long-term prognosis in men than in women in Helsinki. The acute mortality from acute ischaemic heart disease is high in Helsinki when compared with other WHO registers and, in addition, the long-term prognosis seems to be relatively poor in Helsinki.     

Comparison of the influence of acute transmural and nontransmural myocardial infarction on ventricular function

In order to assess the relative impact on left and right ventricular function of nontransmural and transmural acute myocardial infarction (AMI), we performed radionuclide ventriculography in 86 patients (54 men and 32 women) within 16 hours after a first infarct. Nontransmural infarction was present in 19 patients (11 anterior and 8 inferior). Transmural infarction was found in 67 patients (30 anterior and 37 inferior). Left ventricular ejection fractions were higher (0.57 +/- .014 vs 0.46 +/- 0.14, p less than 0.005) and left ventricular end-systolic volume lower (29 +/- 11 vs 42 +/- 20 ml/m2, p = 0.013) in patients with nontransmural infarction compared to those with transmural infarction. Right ventricular ejection fraction also may have been different in the two groups (0.63 +/- 0.15 vs 0.55 +/- 0.13, p = 0.057). In patients with inferior infarction, left and right ventricular ejection fractions were similar in patients with nontransmural and transmural infarction (0.60 +/- 0.09 vs 0.55 +/- 0.10, p = 0.119 and 0.58 +/- 0.14 vs 0.51 +/- 12, p = 0.226). On the other hand, patients with anterior transmural infarction had lower left ventricular ejection fractions (0.36 +/- 0.12 vs 0.54 +/- 0.17, p = 0.003) but similar right ventricular ejection fractions (0.60 +/- 0.13 vs 0.66 +/- 0.14, p = 0.14) compared to those with nontransmural anterior infarction. In 29 additional patients with a history of previous infarction, no differences in any of the parameters studied were found between those with transmural and those with nontransmural infarcts.(ABSTRACT TRUNCATED AT 250 WORDS)     

Surgical intervention in acute myocardial infarction

The goal of surgical reperfusion during the first hours of acute evolving myocardial infarction is to limit the extent of the infarction. This should be reflected by improved ventricular function and low mortality. Over the past 10 years, 440 patients with transmural myocardial infarction and 261 patients with nontransmural myocardial infarction underwent coronary artery bypass graft surgery within 24 hours of peak symptoms. The in-hospital mortality was 5.2% in the transmural group and 3% in the non-transmural group. In a 10-year study period, the mortality in the transmural group rose to 12.5%, while the mortality in the nontransmural group, followed for an 8-year period, rose to a total of 6.5%. The transmural myocardial infarctions in patients revascularized within 6 hours, showed a significantly improved in-hospital mortality of 3.8% compared to an in-hospital mortality of 12% for reperfusion after 6 hours. Anterior transmural areas of myocardial infarctions were reperfused within 6 hours of symptom onset, and demonstrated improved global ejection fraction and regional wall motion. Little improvement was seen if revascularization was instituted later than 6 hours from symptoms except in patients with adequate collateral perfusion of non-total left anterior descending coronary occlusion. Long-term follow-up of patients revascularized for acute myocardial infarction shows a low rate of subsequent reinfarction, incapacitating angina and sudden death. Left ventricular function at the time of cardiac catheterization correlates well with subsequent long-term mortality.     

Sudden death in the year following myocardial infarction : Relation to ventricular premature contractions in the late hospital phase and left ventricular ejection fraction

Both depressed left ventricular ejection fraction and ventricular arrhythmias have been associated with a poor prognosis following acute myocardial infarction. To assess the relative role of each of these parameters in predicting mortality in the early period after hospitalization for myocardial infarction, 24 hour ambulatory electrocardiographic tape recordings and gated cardiac blood pool scans were obtained in 81 patients approximately two weeks after their admission to the hospital for myocardial infarction. Lown class 0 to II ventricular premature contractions during this period were classified as uncomplicated ventricular arrhythmias and Lown class III to V ventricular premature contractions were classified as complicated ventricular arrhythmias. Ejection fraction was calculated from biplane images of gated cardiac blood pool scans. In 36 patients the ejection fraction was ≥ 0.40; only three of these had complicated ventricular arrhythmias. In 45 patients the ejection fraction was < 0.40; 26 of these had complicated ventricular arrhythmias. Eight patients had documented ventricular fibrillation or instantaneous death during a mean 7.0 month (range 2 to 16 months) follow-up period outside the hospital. Although the number of patients studied was small, and there were only eight sudden deaths, life table analysis projected a one year mortality of 66 per cent in patients with complicated ventricular arrhythmias and 31 per cent in patients with an ejection fraction < 0.40. All eight patients who died suddenly were in the subgroup of 26 patients with an ejection fraction < 0.40 and complicated ventricular arrhythmias; none was in the subgroup of 19 patients with an ejection fraction < 0.40 and uncomplicated ventricular arrhythmias (p < 0.02). Although a low ejection fraction may suggest a poor prognosis following myocardial infarction, the presence of complicated ventricular arrhythmias significantly increases the risk of sudden cardiac death in the early period after hospitalization in patients with low ejection fraction.     

High mortality early reinfarction with first nontransmural myocardial infarction

Thirty-eight patients with first nontransmural myocardial infarction were studied to determine prognosis and clinical markers of a high-risk subgroup. We found a high incidence of reinfarction (18%) at a median time of 16 days post nontransmural infarction (seven patients). Reinfarction was uniformly associated with death within 24 hours. A total of 14 patients (37%) either died (eight patients) or required urgent revascularization (six patients). Predominant ST segment depression with presenting nontransmural infarction and a history of prior angina were associated with increased mortality (p less than 0.05 and p = 0.05, respectively). We conclude that patients with nontransmural infarction are at high risk for early recurrent infarction. Patients with history of prior angina and predominant ST segment depression may be at particularly high risk. Reinfarction in these patients is frequently extensive. We recommend that these patients be considered for early coronary angiography.