Balloon Assistance Research Articles

Complex-Shaped Platinum Coils for Brain Aneurysms: Higher Packing Density, Improved Biomechanical Stability, and Midterm Angiographic Outcome

Five to 60% of coiled brain aneurysms recanalize, generally because of coil compaction. In vitro exclusive use of complex-shaped coils allows better packing of the aneurysmal sac and the neck as compared with helical coils. We report a single-center, prospective study using complex coils. Safety, packing density, and recanalization rate were evaluated. Seventy-seven aneurysms were embolized using complex coils alone. Aneurysms had a volume of 265 mm3 (diameter: 7.1+/-3.3 mm) and a neck size of 4.1+/-1.8 mm (range: 1.5-12 mm). Average follow-up available in 31 patients was 10.5+/-7.6 months (range: 3-36 months). Primary angiographic endpoints included aneurysmal recanalization and (re)rupture. Primary adverse events included stroke or death. Complete or near-complete occlusion was achieved in all of the aneurysms but required balloon assistance in 24.6%. The packing density was computed as 37%+/-13%. No rerupture was observed during the follow-up interval. Recanalization was seen in 4 (12.9%) of 31. Two basilar tip aneurysms underwent a safe and complete recoiling. Periprocedural nondevice-related neurologic deficits were seen in 2 (2.9%) of 69 patients. The use of complex-shaped coils allows higher packing density, which may improve the recanalization rate. Basilar tip aneurysms remain a challenge.

A prospective single-center analysis of the safety and efficacy of the HydroCoil embolization system for the treatment of intracranial aneurysms

The HydroCoil embolization system is a helical platinum coil coated with a polymeric hydrogel that expands when it contacts aqueous solutions to increase filling volumes, improve mesh stability, and possibly elicit a healing response within the aneurysm. In this paper, the authors report the 1-year recurrence and complication rates of 67 aneurysms embolized with the HydroCoil system. Sixty-four consecutive patients (67 total aneurysms) with small (< or =7 mm), large (8-15 mm), very large (16-24 mm), and giant (> or =25 mm) aneurysms in the anterior and posterior intracranial circulations were treated with HydroCoils between March 2003 and September 2004. All aneurysms were embolized by the senior author (A.S.B) with HydroCoils alone or in combination with bare platinum coils, until either there was no further angiographic contrast filling of the aneurysm or the microcatheter was pushed out of the dome by the coil mass. Balloon assistance was used in three cases and combined Neuroform stent-coil embolization in eight other cases. To evaluate the safety and 1-year efficacy of the HydroCoil system, periprocedural complications were recorded, and angiographic recurrences were categorized using the Raymond-Roy Occlusion Classification (RROC) system. The 1-year aneurysm recurrence rate independent of size was 15% in patients treated with HydroCoils. Seventy percent of the patients had stable occlusions. The recurrence rate for small aneurysms was 3.7%, and the combined recurrence rate for small and large aneurysms was 6%. Fifteen percent of the aneurysms initially categorized as RROC Type 2 or 3 with stasis of contrast material at the time of initial embolization improved in RROC type, allowing the authors to develop the aneurysm embolization grade to predict recurrence. The neurological complication rate was 14.9%, of which 4.5% represented permanent neurological deficits. The HydroCoil embolization system is safe and provides excellent 1-year occlusion of small and large aneurysms with initial RROC Type 1, as well as those with RROC Types 2 and 3 with stasis of contrast material at the time of embolization. Very large and giant aneurysms were not as successfully occluded with this system. Treatment of large and giant internal carotid artery aneurysms was more likely to result in cranial nerve palsies and postembolization headaches than treatment in other locations. The aneurysm embolization grade the authors developed using the results of this study accurately predicted 1-year recurrence rates based on the immediate postembolization angiographic characteristics of the treated aneurysm.

Intrasaccular combination of metallic coils and Onyx liquid embolic agent for the endovascular treatment of cerebral aneurysms

The aim of this study was to report on a novel technique in which metallic embolization coils were combined with the Onyx liquid embolic agent in the aneurysm sac to achieve a more durable result after endovascular treatment. This therapeutic procedure was performed in selected cases in which, based on the authors' experiences, either coil embolization or Onyx alone would likely have failed. The authors report long-term clinical and angiographic follow-up results in 20 consecutive intracranial aneurysms treated using this combination for defined indications. Twenty aneurysms in 20 patients were treated with a combination of embolic coils and Onyx. Four aneurysms were giant; 13, large; and three, small. This new technique was used when standard Onyx or coil treatment with balloon assistance was determined to involve a higher possibility of recanalization, because either an adjunctive stent insertion could not be performed or the Onyx technique could not be used due to an unsuccessful seal test or intraaneurysm balloon prolapse. In one case, an adjunctive stent was placed before coil placement and Onyx deposition to control the material in the sac of the aneurysm, which had a fusiform neck. All aneurysms were completely occluded after using this technique. No clinical or technical adverse events occurred in any of the cases. Follow-up angiography was performed in all patients: 3-year studies in six patients, 2-year studies in five, and 1-year studies in nine. None of these studies demonstrated aneurysm regrowth or parent artery occlusion. The combination of the embolic coils and the Onyx liquid embolic agent provides very durable aneurysm occlusion for defined indications.

Balloon assistance as a routine adjunct to the endovascular treatment of cerebral aneurysms

Background The technique of BAC is attractive because the balloon theoretically allows for (1) “control” of blood flow in the vessel; (2) improved stability of the microcatheter in the aneurysm; (3) denser packing with coils; and (4) improved delineation of the neck of the aneurysm. The purpose of this communication is to document our outcomes with this technique and help determine if this technique is of benefit. Methods Data on all endovascularily treated aneurysms have been gathered prospectively at our institution since March 2000. The first case of BAC was in November 2000. We have become very liberal in our indications, to the point where all aneurysms are considered for BAC. We document here our results obtained over a 1-year period, during which we treated 56 patients with 60 aneurysms in 58 coiling sessions using only bare platinum coils. Results Balloon-assisted coiling was attempted in 50 (86%) of the 58 coiling sessions. Successful embolizations were achieved in all but 1 patient in whom BAC was attempted. There was one technique-related complication. The packing density for the BAC cases was, on average, 35.7% (median, 34.6%; SD, 14.1%). Follow-up angiography revealed a 13% class 3 recurrence rate. Conclusion With experience, BAC can be used in the endovascular treatment of most cerebral aneurysms. Although complications are associated with its use, we feel that the risk/benefit ratio is favorable. Excellent coil packing density with bare coils is achievable with this technique.

Complications of balloon-assisted coil embolization of intracranial aneurysms

The very experienced endovascular group of Sluzewski and colleagues presents us with a candid assessment of the complications and the short-term clinical and angiography results of balloon assisted coil embolization (BACE) of intracranial aneurysms. Their study is important because other groups have reported a relatively low incidence of complications with this technique; the incidences in the largest six studies in the literature range from 0 to 5.3%. Sluzewski and colleagues treated 71 aneurysms using the balloon-assisted technique. During the 10 years of their study, they treated an additional 756 aneurysms with coils without balloon assistance. In the group treated with balloon assistance, there was a 14.1% incidence of serious procedural complications leading to death in six patients and dependency in four. Of these complications, seven were thromboembolisms and three were intraprocedural ruptures. In contrast, the procedural complication rate in patients treated without balloon assistance was only 3% (death in 1.7% and dependency in 1.3%); 17 of the 23 complications in this group were thromboembolisms and six were procedural ruptures. This difference is very significant statistically, although, of course, the two groups are not comparable given that balloon assistance was used only for large and/or broad-based aneurysms in which CE without balloon assistance was believed to be impossible or had failed.

Temporary Balloon Occlusion during Giant Aneurysm Surgery

We propose this combined balloon occlusion and surgical technique to treat selected patients with large-giant aneurysms not suitable for a pure endovascular or surgical approach. After an occlusion test a non detachable balloon catheter is positioned deflated proximally to the neck of the aneurysm under general anesthesia. The patient is then moved to the neurosurgical room. During the intervention the balloon is inflated and deflated when necessary to allow better surgical control of the aneurysmal sac. With this approach we achieve complete aneurysm occlusion and shorten the surgery time. Since January 2003 we have treated 13 giant aneurysms (ten paraclinoid and three vertebrobasilar) without significant complications related to balloon assistance and a good outcome in all patients.

Late angiographic and clinical follow-up results of 100 consecutive aneurysms treated with Onyx reconstruction: largest single-center experience

We present the long-term clinical and angiographic follow-up results of 100 consecutive intracranial aneurysms treated with Onyx liquid embolic system (MTI, Irvine, Calif.), either alone or combined with an adjunctive stent, in a single center. A total of 100 aneurysms in 94 patients were treated with endosaccular Onyx packing. Intracranial stenting was used adjunctively in 25 aneurysms including 19 during initial treatment and 6 during retreatment. All aneurysms except two were located in the internal carotid artery. Of the 100 aneurysms, 35 were giant or large/wide-necked, and 65 were small. Follow-up angiography was performed in all 91 surviving patients (96 aneurysms) at 3 and/or 6 months. Follow-up angiography was performed at 1, 2, 3, 4 and 5 years in 90, 41, 26, 6 and 2 patients, respectively. Overall, aneurysm recanalization was observed in 12 of 96 aneurysms with follow-up angiography (12.5%). All 12 were large or giant aneurysms, resulting in a 36% recanalization rate in the large and giant aneurysm group. One aneurysm out of 25 treated with the combination of a stent and Onyx showed recanalization. There was also no recanalization in the follow-up of small internal carotid artery aneurysms treated with balloon assistance only. At final follow-up, procedure- or device-related permanent neurological morbidity was present in eight patients (8.3%). There were two procedure-related and one disease-related (subarachnoid hemorrhage) deaths (mortality 3.2%). Delayed spontaneous asymptomatic occlusion of the parent vessel occurred in two patients, detected on routine follow-up. Onyx provides durable aneurysm occlusion with parent artery reconstruction resulting in perfectly stable 1-year to 5-year follow-up angiography both in small aneurysms treated with balloon assistance only (0% recanalization rate) and large or giant aneurysms treated with stent and Onyx combination (4% recanalization rate). Endosaccular Onyx packing with balloon assistance may not be adequate for stable long-term results in those with a large or giant aneurysm. However, the recanalization rate of 36% in these aneurysms is better than the reported results with other techniques, i.e., coils with or without adjunctive bare stents.

Comparison of Dog and Pig Models for Testing Substernal Cardiac Compression Devices

Subtle anatomic differences between species can be a critical consideration when determining whether a given animal model is appropriate for surgical research purposes, especially when testing biomechanical implants. This study compares the effectiveness of two common animal models (dogs and pigs) in testing a balloon based cardiac compression device designed for substernal placement. Pigs were used in acute studies using an infarction model of heart failure, whereas dogs were used in chronic experiments in which heart failure was induced via rapid pacing. Systolic cardiac compression was accomplished in both species using identical balloons inflated between the sternum and right ventricle with every heartbeat. Results showed the device to be much more effective in pigs, where cardiac stroke volumes returned to normal with balloon assistance (14.7 +/- 1.9 to 37.8 +/- 9.2 mL, p < 0.005). Stroke volumes in dogs, however, remained essentially unaltered by balloon activation (28.1 +/- 14.1 to 29.6 +/- 14.7 mL, p = NS). Retrospective comparisons showed pig models to be a much closer approximation to the human anatomy because of a more similar thoracic cavity shape and heart orientation. These findings suggest that certain large animal models should not be used in research in which chest wall shape or cardiac orientation within the thoracic cavity may influence outcomes.

Basilar artery to bilateral posterior cerebral artery 'Y stenting' for endovascular reconstruction of wide-necked basilar apex aneurysms: report of three cases

Endovascular reconstruction of basilar artery (BA) apex aneurysms has been augmented by adjunctive techniques such as balloon and stent assistance. We present three cases of a wide-necked BA apex aneurysm involving the bilateral P1 segments of both posterior cerebral arteries (PCAs) treated by placement of BA to PCA stents bilaterally in a 'Y' configuration to reconstruct the BA apex for effective coil embolization. Three patients (aged 70, 65 and 37 years) with wide-necked basilar artery aneurysms presented for endovascular treatment. All aneurysms had necks that involved the bilateral P1 segments. Each patient was deemed an appropriate candidate for endovascular reconstruction. Patients were pretreated with clopidogrel (75 mg) and aspirin (325 mg) each day for 3 days prior to the procedure. Following induction of general anesthesia, access to the right femoral artery was obtained by placement of a 6F sheath. Intravenous heparin was administered to achieve an activated coagulation time (ACT) of approximately 300 seconds. A 6F guide catheter was placed within the left vertebral artery (VA) in two patients, the right VA in a third. Utilizing over-the-wire (OTW) technique, a microcatheter was advanced into the left P2-P3 junction of the PCA. A 300-cm 0.014-inch microwire was passed through the microcatheter into the distal PCA and the microcatheter was removed. In each case, two neuroform stents were prepared (SMART Therapeutics Inc., San Leandro, CA) and advanced OTW into the PCA with the most acute angle relative to the BA. The initial stent placed was 20 mm in length and was deployed from the P1 segment into the BA. The microwire was pulled retrograde into the BA apex, then advanced though the stent struts and into the right PCA. A second stent, 15mm in length, was advanced OTW through the struts of the previously placed stent. It was then deployed from the P1 into the BA where it overlapped the first stent, resulting in a stent-in-stent 'Y' configuration at the BA apex. A microcatheter was advanced OTW into the BA apex aneurysm and coil embolization proceeded in the usual fashion. Following the procedure, each patient was maintained in the neurosurgical intensive care unit (NICU). All remained neurologically intact. The two elderly patients were discharged to home the morning following the procedure. The third patient suffered an upper GI bleed and was treated an additional 3 days in hospital. Oral clopidogrel (75 mg by mouth) and aspirin (325 mg by mouth) were continued daily for 4 weeks. The 'Y' stent configuration for reconstruction of the BA apex is a safe effective technique in patients with wide-necked BA aneurysms.

Clinical efficacy of metal stents for the treatment of focal abdominal aortic stenosis.

Seven patients (four women and three men) who underwent primary stenting of infrarenal abdominal aortic stenosis over a 4-year period are reported. The patients ranged between 44 and 77 years of age. All were referred for treatment of disabling claudication. Self-expanding stents with balloon assistance were used. A single complication, a retroperitoneal haematoma, requiring surgical intervention occurred in one patient. Patients had either complete resolution of symptoms (five of seven) or a substantial decrease in their claudication symptoms. Primary stenting is a safe and effective treatment for severe abdominal aortic stenosis.

Chirurgie coronarienne à cœur battant et dysfonction ventriculaire gauche

We report our experience with systematic coronary revascularization on the beating heart among patients with left ventricular dysfunction as defined by a left ventricular ejection fraction ⩽40%. Between September 1996 and April 2000, 500 off-pump (OPCAB) revascularizations were performed (95% of all revascularizations for the same time frame, single surgeon). Among them, 76 patients qualified as left ventricular dysfunction and were compared to a similar cohort of 237 patients operated on with cardiopulmonary bypass (CPB) during the same time frame. Age and sex distribution, average preoperative left ventricular ejection fraction and incidence of preoperative unstable angina were the same for both groups. On average, 3.04±0.89 and 2.97±0.69 grafts/patient were made in the OPCAB and CPB groups respectively ( p= NS). Complete revascularization was achieved in 95% of the OPCAB group. Incidence of preoperative intra-aortic balloon assistance were higher in OPCAB (22% versus 9%, p=0.005) whereas postoperative need for new intra-aortic balloon assistance was higher in CPB (8% versus 0%, p=0.02). Incidence of postoperative myocardial infarction was comparable in both groups (6.5% versus 5.5%). Maximal creatinine phosphate of myocardial origin were lower in OPCAB group (beating heart: 32±52%, cardiopulmonary bypass: 45 ± 51%, p = 0.055). Operative mortality was lower in OPCAB group although it did not reach statistical significance (beating heart: 2.6% versus cardiopulmonary bypass: 4.6%, p = 0.3). Complete coronary revascularization on the beating heart can be achieved in patients with left ventricular dysfunction with excellent outcome and low operative mortality.

Iloprost (Ilomédine ®) et circulation extracorporelle avec héparinisation conventionnelle chez un patient ayant une thrombopénie à l'héparine

A 73-year-old female patient was admitted for myocardial infarction. Conventional treatment with heparin was started, intraaortic balloon assistance was required for several days, together with heparin. The platelet counts decreased progressively, from 288 G · 1 −1 on admission to 41 G · 1 −1 on the 16 th day, despite the use of low molecular weight heparin. The in vitro heparin platelet aggregation test remained positive. This aggregation ended on adding iloprost, an analogue of prostacyclin, to the platelet culture bath. A coronary aortic bypass graft was required. An infusion of iloprost was started just after induction of anaesthesia. The initial dose of 0.5 ng · kg −1 · min −1 was gradually increased to 20 ng · kg −1 · min −1. Heparin (400 IU · kg −1) was thereafter added. To maintain a mean blood pressure of a least 50 mmHg, an infusion of up to 10 μg · kg −1 · min −1 of phenylephrine was given. As it was insufficient, an infusion of up to 1 μg · kg −1 · min −1 noradrenaline was required. The iloprost infusion was gradually stopped 15 min before the end of CPB, together with that of noradrenaline. Platelet aggregation tests were positive after protamine had been given, whereas they had been negative during the infusion of iloprost. There was no abnormal postoperative bleeding. An infusion of 2 ng · kg −1 · min −1 was started at the sixth postoperative hour for 48 h, until the coumarin-like agent had started taking its effects. It is concluded that iloprost might be useful for carrying out cardiac surgery in patients with heparin-induced thrombocytopaenia.

Rotational ablation of coronary artery lesions using single, large burrs.

Previous clinical use of the Rotablator in coronary artery disease has involved a sequential increase in burr sizes up to 2 mm in diameter and has often utilized balloon adjunct to achieve an optimal result. We report our experience and describe our technique using a single, large burr (2.25, 2.5, or 2.75 mm diameter) without balloon assistance. The burr size was selected to approximate 70-90 percent of the apparent normal lumen diameter. Thirty-one patients with 36 lesions of complex morphology (eccentric, irregular, calcified, ulcerated, at bends, at bifurcations, completely occluded, as well as balloon failures) were successfully treated with the Rotablator. Results were assessed by computerized quantitative angiography. The percent diameter stenosis (mean +/- SD) for the group was reduced from 69.8 +/- 11.3% to 30.9 +/- 10% (p less than 0.001). The mean absolute diameter stenosis increased from 0.9 +/- 0.3 mm to 2.2 +/- 0.3 mm (p less than 0.001). Angiographically visible dissections were seen in 4 patients and were uncomplicated in 2. One patient had a non-Q-wave myocardial infarction. A fourth patient had a presumed acute occlusion 36 hr after the procedure, necessitating emergency bypass surgery, but without Q waves on the electrocardiogram or wall-motion abnormalities on the echocardiogram. Nitroglycerin was infused through the Rotablator catheter and has considerably lowered the degree and frequency of spasm. No other acute complications occurred. The mean procedure time using a single burr was shorter than when multiple burrs were used: 56.5 vs. 97.3 min, respectively (p less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

Postoperative monitoring of myocardial oxygen tension: experience in 51 coronary artery bypass patients.

Following a preliminary feasibility report, polarographic monitoring of myocardial tissue O2 tension (Pmo2) in 51 coronary bypass patients has been accomplished. In this context, the influence of rapid atrial pacing (RAP), O2 inhalation, and intra-aortic balloon assistance (IAB) was statistically analyzed using Wilcoxon sign-rank and Student's t-tests. Electrodes were implanted in revascularized and nonrevascularized areas for comparison (24.0 +/- 1.1; and 26.3 +/- 1.8 mmHg Pmo2, p, not significant). Increasing myocardial O2 demand with RAP caused a 6% PmO2 drop (p less than 0.01). A 70% O2 inhalation increased Pmo2 by 30% (p less than 0.01). In 5 cases the benefit of IAB was confirmed by a 41% increase in Pmo2 (p = 0.02). These data support the clinical usefulness of polarographic Pmo2 as a measure of regional myocardial oxygenation. In addition to early recognition of intraoperative or postoperative graft failure previously reported, the efficacy of various therapeutic interventions can be more precisely determined.

Radionuclide Assessment of Left Ventricular Function in Patients Requiring Intraoperative Balloon Pump Assistance

Twenty-three surviving patients who were weaned from cardiopulmonary bypass with intraaortic balloon pump assistance returned for follow-up radionuclide left ventricular (LV) function and thallium 201 perfusion studies at a mean of 23 ± 3 months following operation. It was found that despite profound intraoperative myocardial depression requiring intraaortic balloon assistance, 13 patients had no change (within 10%) in the resting LV ejection fraction compared with the preoperative measurement. Among all 23 patients, there was no difference between mean (± standard error of the mean) preoperative and postoperative resting LV ejection fraction (48 ± 4 vs 46 ± 4%, p = not significant [NS]). Only 11 patients had perioperative myocardial infarction documented by new Q waves in the electrocardiogram, by elevation of creatine kinase–MB fraction, or by defects on thallium 201 imaging not explained by documented myocardial infarction before operation. Overall, postoperative resting LV ejection fraction was not different from the preoperative value in patients with perioperative myocardial infarction (44 ± 7 vs 47 ± 5%, p = NS). Postoperative resting LV ejection fraction rose by ≥ 10% compared with preoperative values in 4 patients (3 with aortic valve replacement), remained within the 10% limit in 9 patients, and fell by ≥ 10% in 10 patients (7 with perioperative myocardial infarction). Only 4 out of 16 patients studied at follow-up with exercise radionuclide studies demonstrated a normal LV response to exercise (≥ 5% increase in LV ejection fraction). Thus, among survivors requiring intraaortic balloon pump assistance for weaning from cardiopulmonary bypass, LV performance at rest is frequently preserved. In addition, 11 of the 23 patients had evidence of perioperative myocardial infarction, indicating a component of reversible intraoperative LV dysfunction.

Intra-aortic balloon assistance in cardiogenic shock after myocardial infarction or cardiac surgery.

Sixty-eight patients were referred for consideration of intra-aortic balloon assistance, 55 of whom were accepted. Thirty-one patients were in cardiogenic shock after myocardial infarction and the remaining 24 were cardiac surgical patients. Twenty-three of the myocardial infarct group were established on IABA and all 24 of the cardiac surgical patients. Of the 23 patients with cardiogenic shock after myocardial infarction, 19 showed initial haemodynamic improvement on intra-aortic balloon assistance and 5 (22%) survived to leave hospital. Of the 24 cardiac surgical patients, 15 could not be withdrawn from total cardiopulmonary bypass. With intra-aortic balloon assistance, 11 (73%) could be withdrawn from cardiopulmonary bypass and 5 (33%) were hospital and long-term survivors. The remaining 9 surgical patients were in cardiogenic shock in the early postoperative phase, though 5 showed initial haemodynamic improvement there was only one hospital survivor in this group. Intra-aortic balloon assistance was, therefore, of most value in patients dependent on cardiopulmonary bypass. The survival in patients with cardiogenic shock after myocardial infarction was marginally improved.

Intraaortic Balloon Assistance

Intraaortic balloon (IAB) assistance in 64 patients over 2½ years has resulted in a survival rate of 11% (1 patient) when used alone but 47% when utilized in patients treated surgically (long-term survival, 38% [21 patients]). Patients undergoing coronary artery bypass grafting or aortic valve replacement have a long-term survival of 50% (8 and 9 patients, respectively). The required duration of IAB support has a bearing on the clinical result. Complications have been minimal. Though it was originally developed to assist in the nonoperative management of complications of ischemic heart disease, IAB assistance offers significant promise as an adjuvant to operative therapy for both ischemic and valvular heart disease.

Transthoracic Intraaortic Balloon Cannulation to Avoid Repeat Sternotomy for Removal

Cannulation of the ascending aorta for intraaortic balloon assistance is a practical alternative to the standard transfemoral cannulation in patients with significant aortoiliac occlusive disease. One disadvantage of ascending aortic cannulation has been the requirement for a repeat sternotomy to remove the balloon. This report describes the successful implementation in 2 patients of a technique of ascending aortic balloon insertion and removal that avoids a second sternotomy.

Intraaortic Balloon Assist Through Cannulation of the Ascending Aorta

This report describes a survivor and the technique of intraaortic balloon assistance through cannulation of the ascending aorta. Other sites of balloon insertion and their complications are briefly discussed. The thoracic aorta route for balloon assistance has proved effective and may well be preferable when significant aortoiliac disease exists.

Surgical Management of Ventricular Septal Defects and Mitral Regurgitation Complicating Acute Myocardial Infarction

Sixteen patients were studied subsequent to the development of acute ventricular septal rupture in 7 and severe mitral regurgitation in 9. These lesions occurred within two weeks of acute myocardial infarctions. Intraaortic balloon assistance was initiated when cardiovascular deterioration occurred, and hemodynamic improvement was obtained in all patients. Shunting through a ventricular septal perforation was reduced during balloon assistance, and mitral regurgitation, when present, was decreased. These effects were short-lived, and the patients were subsequently studied with coronary angiography and ventriculography. Two of 3 patients with anterior ventricular septal defect underwent successful surgical correction. Three patients had attempted closure of inferior ventricular septal defect without success. The fourth patient with an inferior ventricular septal defect died of his lesion without any attempt at surgical repair. Four patients with rupture of the papillary muscle were long-term surgical survivors. Coronary artery bypass grafting was carried out when indicated in these patients. Two of 5 patients with papillary muscle dysfunction who underwent operation during the acute period of their infarction were long-term survivors. The findings suggest that the mechanical lesions of mitral regurgitation and ventricular septal perforation are amenable to surgical intervention if a sufficient amount of residual functional muscle can be preserved in the left ventricle. Intraaortic balloon assistance allows a period of time to stabilize the condition of patients with these lesions, to reduce myocardial ischemia, and to carry out studies to determine the degree of associated coronary artery disease and the extent of irreversible myocardial damage. Based on the findings from these studies, surgical procedures may be selected.