Clinical, hemodynamic, and surgical considerations of rupture of the ventricular septum after myocardial infarction

Diagnostic accuracy of a novel 'winking coronary angiographic sign' in patients presenting with ventricular septal rupture complicating acute myocardial infarction

Ventricular septal rupture (VSR) is an uncommon but potentially lethal complication of acute myocardial infarction (MI). Its prompt recognition is essential to permit timely institution of corrective measures. The present study was undertaken to assess the diagnostic accuracy of a novel and unique angiographic sign, the ‘winking coronary sign (WCS)’, for recognizing post-MI VSR. The WCS is defined as partial transient occlusion of the infarct-related culprit artery overlying the site of VSR during ventricular systole with near normal filling in the diastole. A total of 56 patients with post-MI VSR (mean age 60.9 ± 9.9 years, 75% male) were compared with 73 age- and sex-matched acute MI patients without VSR. The extent of coronary artery disease was not different between the two groups, but higher number of patients in the VSR group had thrombolysis in MI grade 3 flow (57.1% vs 34.5%, P 0.01). The WCS was observed in 67.9% of the patients with VSR but in none of the patients without VSR (p < 0.0001), yielding a sensitivity of 67.9% and specificity of 100% for this sign for diagnosing underlying VSR. This demonstrates the potential utility of the WCS for diagnosing VSR in patients in whom the VSR has developed in the time frame between the echocardiography and angiography or has been missed during the initial clinical and/or echocardiographic evaluation.

Repairing the posterior postinfarction ventricular septal defect: a left ventricular approach with a sealant reinforced multipatch technique

An uncommon complication of acute myocardial infarction (AMI), postinfarction ventricular septal defect (PI-VSD), often yields devastating outcomes. Because of the strikingly poor quality of the residual tissue, the repair of PI-VSD poses a surgical challenge and is associated with high operative mortality as well as residual or recurrent shunting. Among the various techniques that have been developed, we prefer a left ventricular approach to repairing PI-VSD by using a multipatch technique reinforced with a sealant as an adjunct to surgical repair. In this method, 3 patches are used: two overlay the left side of the VSD with a sealant (composed of albumin cross-linked to glutaraldehyde) sandwiched between them, whereas a third patch is used to cover the ventriculotomy defect. The rationale is that the use of such a sealant decreases the complications of PI-VSD repair by providing a sturdier surface for suture placement, thereby decreasing suture dehiscence and consequent recurrence of septal rupture. This multipatch technique offers hope in improving the results of the surgical management of PI-VSD.

Relevance of delayed hospital admission on development of cardiac rupture during acute myocardial infarction: study in 225 patients with free wall, septal or papillary muscle rupture

OBJECTIVES

We analyzed the possible relation between the presence of a hospital admission delay (> or =24 h), undue physical effort or recurrence of anginal pain, alone or in combination, with the development of free wall rupture (FWR), septal rupture (SR) or papillary muscle rupture (PMR) in patients with an acute myocardial infarction (AMI).

BACKGROUND

Physical activity as a trigger of FWR in AMI remains controversial, and its contribution to SR or PMR remains unknown. Moreover, the role of ischemia or reinfarction as an additional cause of rupture has not been explored.

METHODS

The incidence of hospital admission delay > or =24 h with maintenance of some ambulatory activity and the incidence of postinfarction angina were analyzed in consecutive patients with a first AMI with (n = 225) or without rupture (n = 1,012 [control group]) over different time periods.

RESULTS

An admission delay > or =24 h occurred in 27 (27.6%) of 98 patients with FWR, 47 (47.0%) of 100 with SR and 14 (51.9%) of 27 with PMR but in only 81 (8%) of 1,012 control patients (p < 0.0001). Information on undue in-hospital effort preceding rupture was available for 111 patients and was present in 17 (32.7%) of 52 with FWR, 9 (18.4%) of 49 with SR and 3 (30%) of 10 with PMR versus only 76 (7.5%) of 1,012 control patients (p < 0.001). Information on postinfarction anginal pain was available for 114 patients with rupture and occurred in 30 (56.6%) of 53 with FWR, 30 (60%) of 50 with SR and 4 (36.4%) of 11 with PMR versus 120 (11.9%) of 1,012 control patients (p < 0.0001). Mean age and incidence of male gender, hypertension, absence of heart failure, single-vessel disease or occlusion of the infarct-related artery were comparable among the groups with FWR, SR or PMR.

CONCLUSIONS

Delayed hospital admission or undue in-hospital physical activity appears to increase the risk of rupture in patients prone to this complication (i.e., a first transmural AMI, absence of overt heart failure and advanced age); recurrence of ischemia/infarction emerges as a potential additional trigger in a proportion of these patients.

Repair of postinfarction ventricular septal defects

Postinfarction ventricular septal defects complicate approximately 1% to 2% of cases of acute myocardial infarction and account for about 5% of early deaths after myocardial infarction. By differentiating the surgical treatment of these acquired lesions from the surgical approaches used to repair congenital ventricular septal defects and realizing the significance of differing anatomic locations of postinfarction ventricular septal defects, techniques have been developed that have improved salvage of patients suffering this catastrophic complication of myocardial infarction. The principles underlying these surgical techniques include (1) expeditious establishment of total cardiopulmonary bypass with moderate hypothermia and meticulous attention to myocardial protection; (2) transinfarct approach to ventricular septal defect with the site of ventriculotomy determined by the location of the transmural infarction; (3) thorough trimming of the left ventricular margins of the infarct back to viable muscle to prevent delayed rupture of the closure; (4) conservative trimming of the right ventricular muscle as required for complete visualization of the margins of the defect; (5) inspection of the left ventricular papillary muscles and concomitant replacement of the mitral valve only if there is frank papillary muscular rupture; (6) closure of the septal defect without tension, which in most instances will require the use of prosthetic material; (7) closure of the infarctectomy without tension with generous use of prosthetic material as indicated, and epicardial placement of the patch to the free wall to avoid strain on the friable endocardial tissue; and (8) buttressing of the suture lines with pledgets or strips of Teflon felt or similar material to prevent sutures from cutting through friable muscle.

Should coronary artery bypass grafting be performed at the same time as repair of a post-infarct ventricular septal defect?

OBJECTIVE

The value of coronary artery bypass grafting (CABG) at the time of repair of a post-infarct ventricular septal defect (VSD) remains controversial. The aim of this study was to analyse the effect of CABG on early mortality and survival following repair of an acquired VSD.

METHODS

Over 23 years, 179 patients, 118 male, 61 female, mean age 66 years (range 43-80), have undergone repair of a post-related VSD in our unit. A total of 29 patients, who predominantly form the earlier part of the series, were operated on greater than 1 month after the infarct and are, therefore, excluded. Coronary angiography was performed in 98 (65.3%) of the remaining 150 patients. Of these, 41 had coronary artery disease (CAD) limited to the infarct-related vessel and 57 had additional significant CAD. Those with CAD limited to the infarct-related vessel were not grafted (Group A). Of those, 40 with significant CAD underwent CABG at the time of VSD repair (Group B) and 17 did not (Group C). In 52 patients the coronary anatomy was not documented (Group D). Risk factors for early mortality were evaluated using logistic regression. Actuarial survival was compared using log rank and Wilcoxon tests. Cox's proportional hazards method was used to determine factors affecting survival.

RESULTS

Overall, 30 day mortality was 32%. CABG did not significantly decrease operative mortality (logistic regression). There was no statistically significant difference in early mortality or actuarial survival between the four groups. CABG was not associated with an increased survival (Cox's method).

CONCLUSIONS

Concomitant CABG at the time of VSD repair does not affect early mortality nor confer survival benefits. There seems to be no demonstrable benefit in revascularisation at the time of repair and, therefore, it may be unnecessary to perform CABG or coronary angiography in these patients.

Traumatic ventricular septal defect

A 26 year old man was admitted to hospital following a traffic accident. He had been sitting in the back of a car without wearing a seat belt. He suffered crush injuries on the anterior chest wall, trunk, and legs. On admission he was awake and cooperative, but restless, and obviously in severe pain. Radiography of the skull, facial bones, chest, spine, pelvis, and legs revealed a shaft fracture of the left femur and tibia and fracture of the 7th and 8th right ribs. The patient was transferred to the University Hospital of Zurich for further assessment and surgical repair of the lower limb fractures three days later. Because of worsening clinical condition with onset of partial respiratory insufficiency and new loud systolic murmur at the left sternal edge, a transthoracic echocardiography was performed, which showed an apical ventricular septal defect. Surgery was performed immediately. The ventricular septal defect was successfully repaired using a Teflon felt patch and interrupted sutures with pledgets, and sealed with glue. At six months' follow up the patient was doing well. Ventricular septal defects after blunt chest trauma occur either because of heart compression between sternum and the spine or because of myocardial infarction. In the present case the ventricular septal defect appeared three days after the accident, probably secondary to a post-traumatic myocardial infarction. Patients with blunt chest trauma and suspicion of cardiac contusion should be monitored carefully.

Emergency department recognition of acquired ventricular septal defect

Acute myocardial infarction associated with ventricular septal defect (VSD) occurs infrequently. When a patient with an acquired VSD presents to the emergency department (ED), prompt recognition is required because definitive treatment can greatly decrease mortality. We present the case of a 75-year-old woman with an acute myocardial infarction and a new heart murmur. The diagnosis of acquired VSD was made by echocardiography in the ED, and emergency surgical correction was arranged.

Hemodynamic profile of a post-infarct ventricular septal defect: left atrial a-waves rather than v-waves may be a prominent feature

The presence of prominent left atrial v-waves following interventricular septal rupture in acute myocardial infarction have been reported in the past. Hemodynamic profile obtained in one particular case highlighted some of the varying aspects of pressure wave, oxygen saturation, and compliance abnormalities that may also be present in such cases. The presence of large left atrial a-waves rather than v-waves was one of the findings.

Postinfarction ventricular septal defect repair: retrospective thoughts and historical perspectives

Evolution of surgical techniques for repair of postinfarction ventricular septal rupture initially involved differentiation of these lesions from prior experience with surgical approaches to congenital ventricular septal defects, which were in the main not applicable. Second, understanding of the differing anatomical locations of postinfarction ventricular septal defects required innovation in terms of the location of the cardiotomy and type of repair necessary to achieve a successful result in any given patient. The gradual appreciation of different clinical courses pursued by patients after postinfarction ventricular septal rupture both in terms of location of the defect and the degree of right ventricular functional impairment has led to increased urgency relative to the timing of surgical repair. The incorporation of specific anatomical concepts of surgical repair and better understanding of the time course of physiological deterioration of patients can ultimately lead to an integrated approach aimed toward improved salvage of patients suffering this catastrophic complication of acute 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.

Role of infarct expansion in rupture of the ventricular septum after acute myocardial infarction: a two-dimensional echocardiographic study

To verify the role of infarct expansion (IE) in ventricular septal rupture (VSR) after transmural acute myocardial infarction (TAMI), topographic parameters were measured using tomographic imaging with two-dimensional echocardiography (2-D echo) and computer-aided analysis in four groups of patients: 8 patients with VSR (Group 1); 24 patients with TAMI but no mechanical complications (Group 2); 11 normal athletes (Group 3); 5 adults with congenital ventricular septal defect (Group 4). Measurements made on end-diastolic outlines of mid-left ventricular (LV) short-axis images included: LV asynergy (akinesis and/or dyskinesis), expansion index (asynergy/nonasynergy-containing endocardial segment length), thinning ratio (asynergic/nonasynergic wall thickness), and new indexes of regional shape distortion (RSD) by quantifying the deviation of the actual asynergic segment from the ideal asynergic arc constructed using the nearly circular nonasynergic contour. In Group 1, clinical IE (hypotension, congestive heart failure, no signs of new infarction) preceded detection of the VSR and portable 2-D echo showed the VSR associated with LV asynergy, marked IE, and RSD. Although Groups 1 and 2 had similar LV asynergy (28.7 vs. 26.9% LV) and ejection fraction (38.9 vs. 41.8%), Group 1 had higher expansion index (1.50 vs. 1.17, p less than 0.05), lower thinning ratio (0.54 vs. 0.67, p less than 0.005), and higher RSD parameters (e.g., peak distortion, Pk or maximum radial distance from the ideal arc, 19.3 vs. 3.9 mm, p less than 0.01; area of distortion, Ad, 7.4 vs. 1.1 cm2, p less than 0.05) than Group 2. Groups 3 and 4 had normal regional and global function and no evidence of expansion, thinning, or RSD. Thus, IE with marked diastolic RSD on an early 2-D echo after TAMI might identify patients at risk for VSR.

Surgical management of postinfarction ventricular septal rupture

Recognition and treatment of patients with ventricular septal rupture following infarction have improved over the past 25 years to the extent that survival with good long-term palliation is achieved in the majority of patients treated surgically for this catastrophic complication of acute myocardial infarction. The small minority of patients who, by the process of selection, are seen for surgical correction of septal rupture several weeks after infarction routinely have repair of the septal defect with an operative risk of less than 10%. With increasingly early diagnosis of septal rupture, the majority of patients are seen for consideration of surgical repair often within hours after septal rupture. Most such patients seen early after septal rupture exhibit cardiogenic shock. Refinement of operative techniques both for suture repair of freshly infarcted myocardium and for repair of defects in different anatomical locations has markedly improved survival in these critically ill patients. Deferral of operation for the patient in cardiogenic shock after septal rupture represents a failed therapeutic strategy. Conversely, emergency operation for the patient with septal rupture and cardiogenic shock has markedly improved survival in this high-risk group. Prolonged intraaortic balloon pump support and deferred operation should be reserved for the uncommon patient who, because of delayed diagnosis or referral, is seen in an advanced stage of multisystem failure in which the risks of early operative intervention involve the function of organs other than the heart.

Doppler echocardiographic features of ventricular septal rupture in myocardial infarction

Doppler echocardiography was used to evaluate the features of interventricular septal rupture in six patients with acute myocardial infarction and to substantiate the hemodynamic data and morphologic findings at surgery or autopsy. Although echocardiographic visualization of the septal rupture was obtained in only two of the six patients, unusual Doppler flow signals were detected in the apical portion of the right ventricle in all six patients. Five patients had unusual flow signals during both systole and diastole; one had such signals only during systole. The location of these unusual flow signals coincided with the site of septal rupture confirmed at surgery or autopsy. The pattern of the flow signals in one cardiac cycle was very similar to that of the pressure difference between the left and right ventricular cavities. These findings indicate that the unusual flow signals represent the left to right shunt flows resulting from septal rupture. In conclusion, Doppler echocardiography may be a very useful tool for diagnosing interventricular septal rupture easily and noninvasively in patients with acute myocardial infarction.

Ventricular septal defect after myocardial infarction: diagnosis by two-dimensional contrast echocardiography

Thirteen patients who had ventricular septal defects (VSDs) after myocardial infarction (MI) underwent two-dimensional echocardiography (2-D echo), with confirmation of the VSD by oximetry. Eight of the patients were male and five were female, ages 51-76 years. Five had anterior and eight inferior MIs. Two-dimensional echocardiography revealed akinesis or dyskinesis of the interventricular septum (IVS) in all 13 patients. In only six could a defect in the IVS be directly visualized. Two-dimensional echocardiographic left ventricular (LV) wall motion abnormalities correlated with ECG and angiographic site of infarction in all patients. Twelve patients had adequate saline contrast studies. Positive LV contrast (microbubbles entering the left ventricle through the VSD) was seen in 11 patients, and negative right ventricular (RV) contrast (washout of the RV bubbles by LV blood crossing the VSD) in five patients; at least one abnormality was present in every patient. The location of the VSD was determined by visualizing a VSD or by the site of the positive LV or negative RV contrast. Oximetry showed VSD shunts of 1.4:1 to 7:1, with no correlation between the degree of negative RV contrast and shunt size. Surgical or pathologic confirmation of VSD was obtained in 12 patients, with agreement of VSD location by 2-D echo in all. Four of the 11 patients who underwent surgical repair died, and two patients died before surgery could be attempted. We conclude tht 2-D echo is a sensitive, rapid and safe technique for diagnosing VSD after MI. Positive LV contrast, with or without negative RV contrast, is more sensitive in the diagnosis and localization of post-MI VSD than direct echocardiographic visualization of the defect.

Ventricular septal rupture: a review of clinical and physiologic features and an analysis of survival

Forty-one patients with postinfarction ventricular septal rupture were cared for in our hospital during 1971-1975. Cardiogenic shock developed after septal rupture in 55% of these patients. Shock was unrelated to site of infarction, extent of coronary artery disease, left ventricular ejection fraction, or pulmonary-to-systemic flow ratio, but mean pulmonary artery pressure was lower in shock than in nonshock patients. These observations suggest that shock was produced mainly by right ventricular impairment. Perioperative survival was much higher in patients who did not have shock preoperatively (14 of 17 [82+]) than in those who did (three of 11 [27%]). Magnitude of shunt, left ventricular ejection fraction, extent of coronary artery disease, and performance of aortocoronary bypass grafting were not distinctly correlated with perioperative survival. After a minimum 4-year follow-up, 76% of the perioperative survivors are alive, and none suffer more than New York Heart Association functional class II disability. All 13 unoperated patients (11 in shock) died within 3 months.

Right ventricular dysfunction in acute ventricular septal defect

Eight patients with acute ventricular septal defect (VSD) receiving early intra-aortic balloon augmentation, cardiac catheterization, and open-heart surgery are described. Because of the large shunts in this group of patients, there was visualization of the right ventricle during left ventriculography which was adequate for qualitative analysis. The following were noted: (1) All patients had severe right ventricular (RV) dysfunction angiographically. (2) RV akinesis noted on angiography was more extensive than the surgical description of RV infarction, although all patients had biventricular infarction at surgery. (3) The RV dysfunction was the major cause of death (two cases) or a contributing factor (three cases). (4) RV papillary muscle rupture was identified in one case.

Management of ventricular septal rupture in acute myocardial infarction

Four patients with rupture of the interventricular septum after myocardial infarction are described. This condition carries a grave prognosis. Surgical repair of the septum is almost always urgently required if the left-to-right shunt is large (QP/WS > 3). Results are better if surgery can be deferred for six weeks to allow the infarcted area to heal and the tissues to be come firmer. This delay may be achieved by using a combination of agents to reduce afterload and to exert a positive inotropic effect. The timing of surgical intervention was an important factor in the survival of three of the four patients.

Two dimensional echocardiographic visualization of ventricular septal rupture after acute anterior myocardial infarction

In three consecutive cases of ventricular septal rupture after acute anterior myocardial infarction, wide angle two dimensional echocardiography readily visualized the septal defect, permitting the defect to be localized and its size estimated. In addition, negative contrast echoventriculography identified a left to right shunt at the ventricular level. The echocardiographic findings were corroborated by cardiac catheterization data in all patients, by perioperative examination in two and by postmortem findings in one patient. Postoperative echocardiographic studies afforded demonstration of the patch closing the defect. In patients with acute myocardial infarction associated with the sudden appearance of a systolic murmur, two dimensional echocardiography should be performed promptly in order to guide the diagnosis and management of these critically ill patients. In some patients with severe cardiogenic shock, in whom a favorable prognosis depends on rapid treatment, two dimensional echocardiography may allow the patient to be taken to surgery immediately without further study.

Abnormal mitral valve motion associated with ventricular septal defect following acute myocardial infarction

It is often difficult to make the clinical distinction between acute mitral regurgitation caused by papillary muscle dysfunction or rupture and ventricular septal defect complicating an acute myocardial infarction. A case of a patient with rapidly progressive congestive heart failure and a loud murmur is presented. Echocardiography strongly suggested the presence of a flail posterior mitral leaflet. However, the patient was subsequently found to have rupture of the interventricular septum. This diagnosis was made with bedside right heart catheterization and was later confirmed by left ventriculography and direct inspection at the time of surgery. The mitral valve apparatus was completely normal. Thus this case demonstrates the apparent lack of specificity of the accepted echocardiographic criteria for flail mitral leaflet and acutely ruptured interventricular septum, and the potential necessity of cardiac catheterization to distinguish between these entities.

Ventricular septal defect following myocardial infarction

Review of the literature since 1970 revealed more than 200 patients who had a ventricular septal defect following myocardial infarction and underwnet operation. Pathogenesis and diagnosis are discussed. The primary therapy is operative repair, which is considered from the standpoint of approach, timing, technique, concomitant coronary artery bypass, mortality, and long-term survival. Operative mortality in those patients operated on less than 3 weeks following perforation remains high (40%) but when it is possible to wait 3 weeks, there is a marked decrease in mortality (6%). Several general principles have evolved for the care of these patients. (1) Operation should be deferred until 3 weeks after infarction if possible. (2) The intraaortic balloon allows preoperative evaluation of the patient with clinical hemodynamic deterioration in the early postinfarction period. (3) The incision should be placed through the infarct. (4) Associated coronary artery or mitral valve disease should be repaired as well.

De subitaneis mortibus. XXIV. Ruptured interventricular septum and heart block

Five patients with acute posterior myocardial infarction developed varying degrees of atrioventricular (A-V) block prior to rupture of their interventricular septums (IVS). In three of these five the times of septal rupture coincided with the resumption of conduced synus rhythm. During the period of A-V block, the only stable escape rhythm appeared to originate in the A-V junctional region, and in two patients early in their course there was evidence of enhanced A-V junctional automaticity. Although the A-V node contained extensive infarction in all five hearts, its distal part, and the entire His bundle and proximal branches appeared to be spared. The anatomical pattern of dissection within the ruptured IVS was similar in three hearts, extending upward to the crest of the IVS and penetrating into the interatrial septum in two of these. Multiple major coronary narrowing were present in all five hearts, especially of a dominating right coronary artery; recent thrombosis was present in the right coronary artery in four of the five cases. The A-V node artery was markedly narrowed by focal fibromuscular dysplasia in three hearts, compounding the ischemia for the A-V node and eliminating one important source of collateral circulation to the interventricular septum.

Posterior rupture of the interventricular septum after acute myocardial infarction: successful early surgical repair

A patient with a large posterior ventricular septal defect complicating an acute inferior myocardial infarction is reported. Because of medically intractable biventricular failure, temporary circulatory assistance was initiated using intraaortic balloon pumping. Emergency coronary angiography, ventriculography, and subsequent operation were carried out. Operative repair involved closure of the septal defect with the use of a Dacron patch, infarctectomy, and aortocoronary bypass grafting and resulted in long-term survival of the patient.

Rupture of ventricular septum or papillary muscle complicating myocardial infarction

Ninety-eight specimens with rupture of some portion of the left ventricle complicating acute myocardial infarction from atherosclerotic coronary disease were studied. In 90, a single structure (so-called isolated rupture) had ruptured as follows: free wall of left ventricle, 52 cases; ventricular septum, 18 cases; a papillary muscle, 20 cases. In eight cases, two structures had ruptured, the most common combination being rupture of ventricular septum and left ventricular wal. Inferolateral location of underlying infarction was the common situation in ruptured papillary muscle, while anteroseptal myocardial infarction was more common in rupture of the ventricular septum. Transmural infarction underlay each case of ruptured ventricular septum, while in ruptured papillary muscle 11 of 20 cases showed subendocardial infarction. There was no association between the type of papillary muscle rupture and the type of infarct. Clinically, collapse of the circulation was common in cases of ruptured ventricular septum and ruptured papillary muscle. Death within one week after rupture was usual when the papillary muscle was involved totally or when the ventricular septum was involved. With partial rupture of a papillary muscle, longer survival (months) was observed in two of ten cases.

Balloon-induced right ventricular outflow obstruction: a new approach to control of acute interventricular shunting after myocardial infarction in canines and swine

Current management of ventricular septal defect (VSD) after myocardial infarction (MI) is aimed at improving left ventricular (LV) performance by afterload reduction as a means of hemodynamic stabilization or shunt control. The current investigation was undertaken to determine whether primary manipulation of right venticular (RV) performance by afterload enhancement was an effective means of reducing MI-VSD shunting. In five open-chest dogs an external LV-RV shunt was created with pulmonary-systemic flow ratios (Qp/Qs) averaging 2.26:1. Inflation of a balloon-tipped catheter in the main pulmonary artery (PA) reduced average QP/Qs to 1.28:1 and shunt flow from 783 to 343 ml/min. However, this increase in RV afterload caused further significant increases in RV systolic and end-diastolic pressure and suggested that deterioration of RV function might be limiting the usefulness of this technique. To investigate whether inotropic support for the RV would overcome this limitation, a similar shunt was created in 11 open-chest swine. We then investigated the effects of dopamine, infused at 24, 60, and 120 mug/min, on QP/QS and other hemodynamic variables both with and without PA balloon inflation. Optimal shunt control was obtained when effects of dopamine were added to those of PA balloon inflation. Shunt flow that had been 1,633 ml/min was reduced to 892 ml/min with the PA balloon and reduced further to 757 ml/min with dopamine, which also lowered RV and LV end-diastolic pressure and reduced total systemic vascular resistance. In four other swine with left anterior descending ligations, PA balloon inflation and dopamine infusion again favorably affected hemodynamics. Epicardial mapping in these swine showed an increase in S-T segment displacement, suggesting that the cumulative effect of these interventions allowed hemodynamic improvement at the expense of enhanced ischemic injury. These data indicate that acute RV outflow obstruction with a balloon catheter is an effective means of temporarily reducing acute ventricular shunting and that dopamine may be a useful pharmacological agent to use with RV afterload manipulation to stabilize a patient prior to transfer to a medical center for more definitive therapy.

Clinical and hemodynamic results of intraortic balloon counterpulsation and surgery for cardiogenic shock

Forty-two patients with cardiogenic shock (CS) secondary to myocardial infarction were treated with intra-aortic balloon pumping (I.A.B.P.). In 14 patients C.S. was associated with ventricular septal defect (V.S.D.) and in four with mitral regurgitation (M.R.) secondary to rupture of the posterior papillary muscle. All patients were resistant to conventional medical therapy. Shock was reversed in 20 of the 24 patients in C.S. without mechanical complications. After 24 to 48 hours of I.A.B.P., cardiax index (C.I.) increased from 1.38 to 2.00 L./min./M2, systolic arterial pressure (S.A.P.) from 83 to 96 mm. Hg, urinary output (U.O.) from 10 to 56 ml. per hour, and pulmonary wedge pressure (P.W.P.) decreased from 22 to 16 mm. Hg. Three patients treated with I.A.B.P. alone survived more than 1 year; of the 13 patients who were balloon dependent, four have undergone emergency surgical procedures and two were long-term survivors. In all patients with mechanical complications, I.A.B.P. resulted in significant clinical and hemodynamic improvement. P.W.P. decreased from 19 to 15 mm. Hg, and U.O. increased from 13 to 38 ml. per hour while S.A.P. remained unchanged. In patients with V.S.D. the pulmonary/systemic flow ratio (P/S) declined from 3.5 to 2.8; in patients with M.R., "V" wave amplitude decreased by 8 mm. Hg. Emergency surgery was performed in 10 patients with V.S.D. and in three patients with M.R. and there were eight long-term survivors (13 to 27 months). It is concluded that I.A.B.P. is an effective means of supporting the circulation in C.S. Of the 42 patients with C.S. treated by combining I.A.B.P. and emergency surgery, 13(31%) were long-term survivors (20 +/- 6 months).

Intraventricular free wall dissection causing acute interventricular communication with intact septum in myocardial infarction

This report delineates a previously unrecognized complication of acute myocardial infarction, an intraventricular wall dissection producing interventricular communication without septal perforation. The clinical, hemodynamic, and pathologic features of this unique condition are documented, as well as the factors important in the mechanism of its production.

The hemodynamic simulation of mitral regurgitation in ventricular septal defect after myocardial infarction

The development of a ventricular septal defect (VSD) following myocardial infarction is an uncommon complication which clinically can be confused with mitral insufficiency due to infarction of a papillary muscle. The clinical and hemodynamic records of six patients with documented acute VSD secondary to myocardial infarction were analyzed to determine which descriptors would be of value in clinically separating these two entities. All six of our patients had a right heart catheterization showing an oxygen step-up consistent with a VSD, and five had a large pulmonary wedge V wave suggesting concomitant mitral insufficiency. The echocardiogram showed only nonspecific chamber enlargement. Since these patients were being considered for open heart surgery to close the VSD, left and right cardiac catheterization including selective coronary arteriography was done. Despite large V waves being present in the pulmonary wedge and/or left atrial pressure tracing in five of the six patients, no mitral insufficiency was present on the left ventricular cineangiograms. It is concluded that a large pulmonary wedge and/or left atrial V wave does not necessarily indicate mitral insufficiency. Since both a VSD and mitral insufficiency are surgically correctable, patients who develop new holosystolic murmurs following myocardial infarction should have complete right and left heart catheterizations with LV angiography for accurate diagnosis if surgical correction of the lesion is contemplated.

Echocardiographic manifestations of postinfarction ventricular septal rupture

The echocardiographic features of three patients with postinfarction ventricular spectal rupture are described. All patients showed a decreased or paradoxical motion on the ventricular septum, and two of the patients demonstrated an unusual motion of the tricuspid valve. There were no abnormalities in mitral valve motion. The echocardiogram can be helpful in the diagnosis of postinfarction ventricular septal rupture and can assist in distinguishing this condition from acute disruption of the mitral valve complex.

Diagnosis of ventricular septal defect in acute myocardial infarction without cardiac catheterization

Five patients with acute myocardial infarction and a systolic murmur suggestive of ventricular septal rupture or mitral regurgitation have been examined by external vascular isotope dilution curves over the chest after i.v. injection of 125I-hippuran. In three patients these isotope dilution curves showed signs of left-to-right shunting of blood, and subsequent autopsy demonstrated the presence of ventricular septal defect. In two patients there was no sign of left-to-right shunting, and these patients recovered.

Echocardiographic findings of ventricular septal rupture in acute myocardial infarction

Echocardiograms were recorded both before and after the clinical appearance of an autopsy-confirmed interventricular septal rupture in a patient with an acute myocardial infarction. The major findings were related to the upper portion of the interventricular septum. Before rupture, this portion of the septum was relatively akinetic with a slight anterior motion during systole, whereas after rupture there was a marked increase in the amplitude of septal motion with abrupt posterior motion occurring with the onset of ventricular diastole.

Myocardial revascularization combined with intracoronary infusion of hyperosmolar solution in the early management of postinfarction ventricular septal defect. Report of a case

A patients is described with postinfarction ventricular septal defect in whom the perforation was successfully closed within 24 hours of septal rupture. This presents the second such case reported in the literature. Adjunctive measures consisting of myocardial revascularization and intracoronary infusion of mannitol were thought to be important in the successful outcome of the operative procedure. The importance of complete preoperative cardiac catheterization with coronary arteriography is stressed. The theoretical role of endothelial and myocardial cellular edema as a cause of depressed myocardial function immediately following an ischemic insult is proposed as a practical consideration in the high mortality associated with this condition. Methods used to prevent or reverse such cell swelling are described. The details of the operation in which viable ventricle myocardium was used to fill the septal defect are presented.

Echocardiographic observations on ventricular septal rupture complicating acute myocardial infarction

Echocardiograms were performed on three patients with ventricular septal rupture complicating myocardial infarction. The pulmonary artery mean pressure was 30 mm Hg or more in all three patients. The size of the ventricular septal defect, determined at operation or autopsy, was 2 cm or greater in each patient. The salient echocardiographic abnormality was dilatation of the right ventricle. The direction of septal motion was normal in all the patients. The left atrial diameter was slightly increased in one patient and was normal in the other two. In one patient, and unusual pattern of mitral valve motion was seen. Complete closure of the reopening of the valve. This pattern was suggestive of increased blood flow through the mitral valve. Although some of these findings are nosspecific, the combination of echocardiographic findings may provide useful clues to the diagnosis of septal perforation.