Carvedilol for prevention of restenosis after directional coronary atherectomy : final results of the European carvedilol atherectomy restenosis (EUROCARE) trial.

BACKGROUND: In addition to its known properties as a competitive, nonselective beta and alpha-1 receptor blocker, carvedilol directly inhibits vascular myocyte migration and proliferation and exerts antioxidant effects that are considerably greater than those of vitamin E or probucol. This provides the basis for an evaluation of carvedilol for the prevention of coronary restenosis. METHODS AND RESULTS: In a prospective, double-blind, randomized, placebo-controlled trial, 25 mg of carvedilol was given twice daily, starting 24 hours before scheduled directional coronary atherectomy and continuing for 5 months after a successful procedure. The primary end point was the minimal luminal diameter as determined during follow-up angiography 26+/-2 weeks after the procedure. Of 406 randomized patients, 377 underwent attempted atherectomy, and in 324 (88.9%), a

Randomized comparison of primary stenting and provisional balloon angioplasty guided by flow velocity measurement. Doppler Endpoints Balloon Angioplasty Trial Europe (DEBATE) II Study Group.

BACKGROUND: Coronary stenting improves outcomes compared with balloon angioplasty, but it is costly and may have other disadvantages. Limiting stent use to patients with a suboptimal result after angioplasty (provisional angioplasty) may be as effective and less expensive. METHODS AND RESULTS: To analyze the cost-effectiveness of provisional angioplasty, patients scheduled for single-vessel angioplasty were first randomized to receive primary stenting (97 patients) or balloon angioplasty guided by Doppler flow velocity and angiography (523 patients). Patients in the latter group were further randomized after optimization to either additional stenting or termination of the procedure to further investigate what is "optimal." An optimal result was defined as a flow reserve >2.5 and a diameter stenosis <36%. Bailout stenting was needed in 129 patients (25%) who were randomized to balloon angioplasty, and an optimal result was obtained in 184 of the 523 patients (35%). There was no significant difference in event-free survival at 1 year between primary stenting (86.6%) and provisional angioplasty (85.6%). Costs after 1 year were significantly higher for provisional angioplasty (EUR 6573 versus EUR 5885; P:=0.014). Results after the second randomization showed that stenting was also more effective after optimal balloon angioplasty (1-year event free survival, 93.5% versus 84.1%; P:=0. 066). CONCLUSIONS: After 1 year of follow-up, provisional angioplasty was more expensive and without clinical benefit. The beneficial value of stenting is not limited to patients with a suboptimal result after balloon angioplasty.

Laser angioplasty of restenosed coronary stents: results of a multicenter surveillance trial. The Laser Angioplasty of Restenosed Stents (LARS) Investigators.

OBJECTIVES: This study evaluated safety and efficacy of excimer laser angioplasty for treatment of restenosed or occluded coronary stents. BACKGROUND: Balloon angioplasty of in-stent restenosis is limited by a high recurrence rate. Debulking by laser angioplasty is a novel concept to treat in-stent restenosis. METHODS: A total of 440 patients with restenoses or occlusions in 527 stents were enrolled for treatment with concentric or eccentric laser catheters and adjunctive balloon angioplasty. RESULTS: Laser angioplasty success (< or =50% diameter stenosis after laser treatment or successful passage with a 2.0-mm or 1.7-mm eccentric laser catheter) was achieved in 92% of patients. Adjunctive balloon angioplasty was performed in 99%. Procedural success (laser angioplasty success followed by < or =30% stenosis with or without balloon angioplasty) was 91%. There was neither a significant difference in success with respect to lesion length, nor were there differences between small and large vessels or native vessels and vein grafts. Success was higher and residual stenosis lower using large or eccentric catheters. Serious adverse events included death (1.6%, not directly laser catheter related), Q-wave myocardial infarction (0.5%), non-Q-wave infarction (2.7%), cardiac tamponade (0.5%) and stent damage (0.5%). Perforations after laser treatment occurred in 0.9% of patients and after balloon angioplasty in 0.2%. Dissections were visible in 4.8% of patients after laser treatment and in 9.3% after balloon angioplasty. Reinterventions during hospitalization were necessary in 0.9% of patients; bypass surgery was performed in 0.2%. CONCLUSIONS: Excimer laser angioplasty with adjunctive balloon angioplasty is a safe and efficient technology to treat in-stent restenoses. These data justify a randomized comparison with balloon angioplasty.

Effect of methylprednisolone sodium succinate on hypoxic heart muscle.

The ability of 30 mg/litre methylprednisolone sodium succinate (MPSS) to modify the effects of hypoxia on isolated Langendorff-perfused rat hearts was investigated. When perfused under hypoxic conditions (pO2 less than 0.8 kPa[6 mmHg]) these hearts lose intracellular enzymes, including creatine phosphokinase (CPK) and succinic dehydrogenase (SDH). The size of the extracellular space is enhanced, the cells gain Na+ and Ca2+ and lose K+, and the endogenous stores of ATP and CP are depleted. Initially the resistance to flow in the coronary circulation falls but after 75 min of hypoxic perfusion it increases so that coronary flow is reduced. MPSS failed to prevent hypoxic muscle from either gaining Na+ and Ca2+ or losing K+. It did, however, delay the release of CPK and SDH from the hypoxic muscle, prolong the phase of increased coronary flow, and decrease the rate of depletion of the energy-rich phosphate stores. MPSS potentiated the hypoxic-induced gain in Ca2+. Whilst the effects of MPSS on coronary flow and tissue Ca2+ were probably due to the steroid part of the complex, the other changes, including the protection of the ATP and CP stores and the delayed enzyme release, were probably due to the presence of the sodium succinate.

Multiple cerebral aneurysms and cardiac myxoma.

Neurological signs are a frequent manifestation of left atrial myxoma, but the association of cardiac myxoma with multiple cerebral aneurysms is rare. A case of left atrial myxoma was detected in the course of a long-lasting psychiatric and neurological illness. Four-vessel study showed the presence of multiple saccular and fusiform aneurysms, regularly and almost symmetrically distributed. The intracardiac mass was removed, and the patient improved.

Influence of preoperative left ventricular function on results of homograft replacement of the aortic valve for aortic stenosis.

The effect of preoperative left ventricular function on early and late prognosis was assessed in 103 patients with aortic stenosis who underwent left ventricular cineangiography before homograft replacement of the aortic valve. The patients were separated into two groups: Group A (58 patients) with an ejection fraction of 0.46 or more and Group B (45 patients) with an ejection fraction of 0.45 or less. The two groups were compared with respect to clinical and hemodynamic data as well as operative result. There was poor correlation between clinical data and left ventricular function. In Group A there were three early deaths (5.2 percent) and three late deaths (5.2 percent) compared with no early and six late deaths (13.3 percent) in Group B during the follow-up period of 12 to 102 months (mean 43 months). Most patients in Group B showed considerable symptomatic improvement but less than that observed in Group A. Forty-two patients (13 in Group A and 29 in Group B) underwent repeat cardiac catheterization and coronary angiography. Improvement in left ventricular function as assessed by radial analysis of segmental wall motion and ejection fraction was observed in 20 of the 29 patients in Group B. Failure of left ventricular function to improve was associated with additional coronary artery disease in the majority of patients. It is concluded that poor left ventricular function does not increase the risk of aortic valve replacement for aortic stenosis and that improvement in left ventricular function can be expected in the majority of patients.

Comparison of the effects of a controlled-release formulation of isosorbide-5-mononitrate and conventional isosorbide dinitrate on exercise performance in men with stable angina pectoris.

Thirty-three men with stable exercise-induced angina pectoris entered a randomized, double-blind, crossover study in which controlled-release isosorbide-5-mononitrate 60 mg once daily was compared with conventional isosorbide dinitrate 20 mg 3 times daily. Each drug was given for 2 weeks. Twenty-eight patients completed the study and data on exercise variables are available in 23 patients. Treatment with either drug resulted in significant antianginal effects, when measured 6 hours after a single dose and after 2 weeks of therapy compared with baseline placebo; however, there were significantly fewer signs of myocardial ischemia during treatment with isosorbide-5-mononitrate. There was no evidence of tolerance to either drug treatment but a significant attenuation of resting blood pressure (but not of exercise blood pressure) was observed with both drugs. Headache was the only clinically significant adverse event during therapy and it occurred more frequently in the isosorbide dinitrate treatment group (p less than 0.05 vs placebo); 3 such patients had to withdraw from the study because of headache. Thus, once-daily, controlled-release isosorbide-5-mononitrate appears as effective as conventional isosorbide dinitrate 3 times daily in patients with stable angina pectoris. The once-daily administration is convenient and improves patient compliance.

Evaluation of 2 intravenous thrombolytic agents (anisoylated plasminogen streptokinase activator complex versus streptokinase) in patients with acute myocardial infarction.

Ten patients with symptoms of acute myocardial infarction of less than 6 hours duration were randomised to receive either anisoylated plasminogen streptokinase activator complex [APSAC] (30U) or streptokinase (1,500,000U) intravenously. The aims of the study were to compare the angiographic patency of the infarct-related coronary arteries and to monitor drug safety and tolerance for up to 24 hours. The left anterior descending artery was occluded in 3, the left circumflex in 3 and right coronary artery in 4 patients. Time between onset of pain and treatment ranged from 150 to 330 minutes. At 90 minutes, 8 patients, 3 of 5 (60%) of the APSAC group and all of the streptokinase group, had patent arteries. No significant differences were found in measurements of coagulation. There were no haemorrhagic complications. One patient of the APSAC group had reinfarction 6 hours after treatment and died in cardiogenic shock. APSAC seems safe and is easier to use than streptokinase, and both agents result in patency in the majority of patients, although too few patients were included to allow a valid comparison. However, thrombolysis should be considered only a temporary solution in acute myocardial infarction, associated mainly with 3-vessel disease.

Influence of preoperative left ventricular function on results of homograft replacement of the aortic valve for aortic regurgitation.

The effect of preoperative left ventricular function on eraly and late prognosis was assessed in 69 patients with aortic regurgitation who underwent homograft replacement of the aortic valve. Patients were divided into two groups: Group A (38 patients) had an ejection fraction of 0.46 or more and Group B (31 patients) had an ejection fraction of 0.45 or less. Clinical data, hemodynamic data, and operative results were compared in the two groups. In Group A there was one early death (2.6%) and there were two late deaths (5.3%) compared to two early deaths (6.5%) and seven late deaths (22.6%) in Group B during a follow-up period of 13 to 98 months (mean, 49 months). Actuarial analysis showed a 94% survival at 6 years in Group A compared to 80% in Group B. Twenty-four patients were reinvestigated by repeat cardiac catheterization and coronary angiography at a mean time of 38 months following valve replacement. Left ventricular function was assessed by computerized quantitative radial analysis of segmental wall motion. Improvement in left ventricular function occurred in eight of the 14 patients reinvestigated in Group B, and appeared to be closely related to the etiology of the initial valve lesion. Despite the higher mortality rate in patients with poor left ventricular function, most derived considerable benefit from operation.

Atrioventricular valve repair using externally adjustable flexible rings.

Initial results obtained with a new flexible ring, adjustable from outside of the heart after interruption of extracorporeal circulation, are presented. Twenty-five rings have been inserted in 20 patients, 14 in the mitral position and 11 in the tricuspid position. In 8 of the 14 patients receiving mitral annuloplasty, other standard mitral valve repair techniques were used. Adjustment, assisted by intraoperative transesophageal color Doppler echocardiography, was done for 10 (71%) of the mitral rings and for 8 (73%) of the tricuspid rings. Residual mitral regurgitation disappeared or became minimal in 9 (90%) patients, and a mild regurgitation remained in 1. In all patients who received tricuspid rings regurgitation was abolished after the adjustment. There was no hospital or late mortality. After a maximum follow-up of 6 months results are comparable in the tricuspid and mitral positions and echocardiographic evaluation revealed stable competent valves in all patients but one, who underwent reoperation because of failure of a mitral valve chordae shortening procedure. The use of externally adjustable rings for the mitral and tricuspid valves is a safe alternative for atrioventricular valve annuloplasty and has the additional advantage of reducing postrepair regurgitation.

Longstanding traumatic tricuspid regurgitation with severe right ventricular failure.

A very unusual case of traumatic tricuspid regurgitation is reported, with severe symptoms of right ventricular failure, extreme dilatation of the right heart, echocardiographic and angiographic criteria of major tricuspid regurgitation, and severe right ventricular systolic dysfunction. The patient was referred for heart transplantation, on the assumption that conventional surgery was not possible. After careful evaluation, as the patient had normal pulmonary artery pressure and resistance, a tricuspid valve was replaced with good surgical outcome.

The glycoprotein IIb/IIIa receptor inhibitor (abciximab) in ST-segment elevation myocardial infarction.

A successful therapy is presented using the antiplatelet agent abciximab, alone, in an ST-segment elevation acute myocardial infarction. The patient was treated in a center with permanent catheterization facilities. Clinical trials are necessary to validate the efficacy and the cost-effectiveness of this clinical decision and therapeutic option.

Coronary angioplasty in Portugal.

Coronary angioplasty began in Portugal in 1984 at the Santa Cruz Hospital and has developed progressively, being practiced in twelve hospitals since 1997. The number of patients with ischemic cardiopathy per annum that are submitted to this form of therapy has also increased. The increase is mainly in the past five years, from 684 procedures in 1993 to 3,005 in 1997. With regard to new devices, the use of intracoronary stents, which began in 1990 in Portugal is currently practised in all hospitals, 2,364 stents were implanted in 1997. This development of angioplasty has made it definitively established in Portugal, even in hospitals without cardiac surgery, as an alternative treatment to coronary surgery and medical treatment. In the absence of a national registry of interventional cardiology, which allows data to be gathered on the type of patients and the clinical situations in which angioplasty is used, it is not possible to ascertain whether medical treatment or surgical treatment have gained patients. Without evidence that surgery has decreased, it is presupposed that the increase in angioplasty is mainly the result of a greater number of diagnostic coronariographies. The current continued growth which has been observed, gives the impression that the development of the early diagnostic suspicion of coronary disease, easier access to coronariographies even in district hospitals and the improvement of technical conditions and manpower in central hospitals will sustain the increase in angioplasty in coming years. In becoming the solution to the problem of restenosis, angioplasty may undisputedly become the most promising therapeutic alternative in ischemic cardiopathy, in parallel with hypercholesterolemia control and other coronary risk factors.

[Intervention cardiology in acute myocardial infarct]. / Cardiologia de intervenção no enfarte agudo do miocárdio.

At the time when thrombolysis in acute myocardial infarction is well established, some controversy still exists about the exact role of coronary angioplasty in this setting. The rationale for a more aggressive intervention after thrombolysis lies in the fact that in a high proportion of the patients the infarct related artery remains occluded or there is a significant residual stenosis. In the latter case this would predispose to reocclusion and recurrent infarction and, by impeding coronary flow, it would limit the extent of myocardial salvage and the rate of myocardial healing. Angioplasty (PTCA) can be performed as an early procedure or late after thrombolysis. Early PTCA can be done as a primary procedure (Direct PTCA), following successful IC or IV thrombolysis (Immediate PTCA) or following unsuccessful thrombolysis (Rescue or salvage PTCA). Late PTCA can be used as a prophylactic (Deferred PTCA) selectively for recurrent angina or positive functional provocative test for ischemia. Direct PTCA has shown to be highly successful both in totally occluded arteries and in subtotal occlusions, with reduced incidence of access site, artery intimal and intramyocardial hemorrhage, but requires a 24-hour cardiac catheterization stand-by with high costs. It is certainly indicated in patients with contra indications to thrombolysis. Immediate PTCA has been evaluated in 3 large scale multicenter randomized controlled trials (TAMI, TIMI II A and ECSG) after IV rt-PA, and although with different design, they concluded that immediate PTCA offers no advantage over a deferred strategy.(ABSTRACT TRUNCATED AT 250 WORDS)

[Evaluation of myocardial reserve as a contribution to the surgical indication in aortic insufficiency]. / Avaliação da reserva miocárdica como contribuição para a indicação cirúrgica na insuficiência aórtica.

Surgical indication in symptomatic patients with chronic aortic regurgitation is mandatory, but it is sometimes doubtful in two extreme situations: asymptomatic patients and patients with severe left ventricular dysfunction. The authors review the contribution of radionuclide angiography (RNA) for the selection of surgical indication in these two groups of patients, by the evaluation of baseline ejection fraction and of contractile reserve, defined as ejection fraction variation with exercise in asymptomatic patients and with inotropic stimulation in patients with severe left ventricular dysfunction. In asymptomatic patients, RNA may contribute to the selection of patients with incipient ventricular dysfunction (manifested only with exercise), in which a closer follow-up should be obtained, to propose surgery early when baseline ventricular dysfunction appears. In patients with severe ventricular dysfunction, RNA may give us some clues on the probability of left ventricular function recovery after surgery, contribution to the decision of proposing conventional surgery or heart transplant. The authors shortly review preliminary data on the follow-up of 48 patients with chronic aortic regurgitation, studied by RNA with exercise (44 patients) or dobutamine infusion (4 patients) at the Hospital de Santa Cruz from 1987 to 1991. Fifteen of these patients have been submitted to surgery.

[Diagnosis of ischemia and survival after myocardial infarction using perfusion scintigraphy with exercise thallium-201. Relationship with electrocardiographic and angiographic findings]. / Diagnóstico de isquemia e viabilidade após enfarte do miocárdio pela cintigrafia de perfusão com tálio-201 após esforço. Relação com achados electrocardiográficos e angiográficos.

OBJECTIVE: To review the experience of the laboratory on exercise-redistribution thalium-201 scintigraphy after myocardial infarction, and to compare scintigraphy results with those of exercise test and coronary angiography. DESIGN/SETTING/PATIENTS: Retrospective analysis of data from scintigraphy, exercise test and coronary angiography from all patients evaluated after myocardial infarction at Nuclear Medicine Department of Instituto do Coração with treadmill exercise-redistribution thallium-201 SPECT, if they were also submitted to cardiac catheterization. These criteria were met by 185 patients, studied between March 1988 and July 1993. MATERIAL AND METHODS: Micro-Delta system with a Siemens Orbiter gamma camera. Visual analysis of intensity and reversibility of perfusion defects in 5 segments per patient, using oblique reconstruction of images. RESULTS: Perfusion defects were found in 97% of patients and in 418/925 analysed segments. Variable degrees of reversibility were found in 78% of patients. On patients with single-vessel disease, vessel occlusion was associated with a slightly higher prevalence of reversibility (81% vs 71%; ns), and, for anterior infarcts, also with a higher prevalence of defects in areas supposed to be remote territories (44% vs 15%, p < 0.05). For 159 patients with a conclusive exercise test, ability of exercise test in diagnosing defects with reversibility was studied. Negative predictive accuracy of exercise test was poor (33%). Angina was 86% specific. Use of isolated ST depression, depression plus elevation or isolated ST elevation as criteria for a positive test result in a progressive improvement of sensitivity, but at cost of a decrease in specificity, more marked when using isolated ST elevation. CONCLUSIONS: Thallium scintigraphy revealed perfusion defects with some degree of reversibility in a large number of patients studied after myocardial infarction, even when considering single-vessel disease or occluded infarct-related artery. Electrocardiographic treadmill exercise test had a poor negative predictive accuracy, being reasonably sensible in multivessel disease, but poorer in single vessel disease. After infarction, typical angina should probably be also considered as criterion for ischemia, regardless of electrocardiographic changes. In a perspective of eventual use of revascularization after infarction, thallium-201 scintigraphy is a valuable tool, and should probably be considered in most patients.

[Response of the left ventricular ejection fraction,assessed by by radionuclide angiography, to inotropic stimulation: its relationship with the reversibility of perfusion defects in thallium-201 scintigraphy with overload-reinjection protocol]. / Resposta da fracção de ejecção ventricular esquerda por angiografia de radionuclidos à estimulação inotrópica: sua relação com a reversibilidade dos defeitos de perfusão na cintigrafia com tálio com protocolo de sobrecarga-reinjecção.

BACKGROUND: Reversibility of perfusion defects and left ventricular (LV) ejection fraction (LVEF) response to low-dose catecholamines may reflect complementary aspects of myocardial viability, in patients with CAD and LV dysfunction in whom revascularization is considered. OBJECTIVE: To evaluate the relationship between LVEF response to inotropic stimulation with adrenaline (delta LVEF) and myocardial perfusion. DESIGN AND SETTING: Prospective study in a cardiology department with referral for revascularization and transplantation. PATIENTS: 45 patients (pt) with compromised LVEF (< 45%) after myocardial infarction (MI). METHODS: Radionuclide ventriculography at baseline and during graded adrenaline infusion until 12 micrograms/min: an empirical cut-off value of delta LVEF of 8% was used to define groups with (CR+) or without (CR-) contractile reserve. Stress-reinjection 201TI SPECT: perfusion was classified with a weighted score based on visual analysis of extent and intensity of thallium uptake in five major myocardial segments, with results expressed as percent of myocardium classified as normal (%N), with fixed defects (%F), and with reversibility (%R). MAIN RESULTS: Groups CR+ (23 pt) and CR- (22 pt) had similar baseline LVEF (29.6 +/- 7.4 and 26.4 +/- 8.1), while delta LVEF was respectively 13.6 +/- 4.6 and 2.9 +/- 3.3. When compared to the other group, CR+ patients had, in average, 1.0 segment more with definite reversibility and 1.6 segments less with fixed defects; in terms of percentage of myocardium, CR+ patients had more extensive reversible areas (%R: 15.3 +/- 11.7 vs 4.7 +/- 5.0, p < 0.001), smaller irreversible areas (%F: 30.7 +/- 14.5 vs 45.6 +/- 16.1, p = 0.02) and similar extent of normal areas (54.0 +/- 14.6 vs 49.7 +/- 16.4). Patients with more extensive fixed defects had worse delta LVEF in response to adrenaline (p < 0.002, r = -0.45). Greater %R was positively correlated with delta LVEF (p < 0.02, r = 0.35). In all patients, delta LVEF with adrenaline was superior or equal to (%R/2)-10. No patient with %R > or = 15 had delta LVEF < 8%. However, ten patients had delta LVEF > or = 8% despite lesser degrees of %R. CONCLUSION: Our data suggest a clear association between myocardial inotropic reserve and the extent of potentially viable myocardium (as evaluated by stress-reinjection thallium SPECT), in patients with left ventricular dysfunction after myocardial infarction. Further assessment is needed to clarify the relative role of radionuclide ventriculography with inotropic stimulation in viability evaluation, notably with inclusion of regional wall motion information and with reassessment of patients after revascularization, when performed.

[Does the modified Bruce protocol induce physiological stress equal to that of the Bruce protocol?]. / O protocolo de Bruce modificado induz stress fisiológico igual ao do protocolo de Bruce?

OBJECTIVE: To determine if the physiological stress induced by the modification of Bruce protocol used in our hospital is equivalent to the original protocol. DESIGN: Retrospective analysis of clinical history, physical examination and stress test of apparently healthy individuals submitted to cardiac check up. SETTING: Outpatient private cardiological clinical. PARTICIPANTS: Sequential sampling of 80 individuals apparently healthy, submitted to cardiac check-up between April 1988 and September 1992. MATERIAL AND METHODS: Comparison of heart rate, blood pressure and double product progression, as well as time of exercise of individuals studied by the Bruce protocol (group A: n = 51) with the same data of individuals tested by the modified Bruce protocol (group B: n = 29). MEASUREMENTS AND MAIN RESULTS: The first stage of group A protocol provokes a superior physiologic stress than group B protocol, since there are bigger increments on heart rate (28.8 +/- 9.9 vs. 20.2 +/- 11.2 bpm; p < 0.01), blood pressure (27.0 +/- 11.3 vs. 14.3 +/- 11.4 mmHg; p < 0.0001) and, consequently, higher double products. In submaximal stages with the same speed and grade on the treadmill the hemodynamical stress is similar in both groups. At peak exercise, group A attains higher values on systolic blood pressure (197.1 +/- 9.5 vs. 188.8 +/- 10.4 mmHg; p < 0.001), double product (34330.4 +/- 2191.8 vs. 33060.9 +/- 2049.8; p = 0.01) and corrected exercise time also higher than estimated (929 +/- 91 vs. 818 +/- 94 sec; p = 0.02). It could be found that more individuals on group A (76% vs. 48%; p = 0.02) could complete the stage of 6.8 Km/h x 16% (stage IV on Bruce protocol and V on modified Bruce protocol. CONCLUSIONS: Modified Bruce protocol has a lighter initial increment, but decreases moderately the capacity of peak exercise due to peripheral fatigue secondary to the first stage of low intensity. Bruce protocol has a higher initial increment but permits to attain higher peak exercise intensities. Bruce protocol seems more adequate to individuals with good physical capacity and the modified Bruce protocol to individuals moderately limited in their functional capacity due to bad physical fitness or illness.

[Occlusion of the common branch of the left coronary artery. Clinical and angiographic characteristics and review of the literature]. / Oclusão do tronco comum da coronária esquerda. Aspectos clínicos, angiográficos e revisão da literatura.

The clinical and angiographic aspects of seven patients with left main stem coronary artery occlusion diagnosed within the first ten thousand coronary angiographies performed at our Hospital, are reported. The prevalence found (0.07%), is similar to that previously described (0.03 to 0.42%). Left main coronary artery occlusion is always an acute phenomenon with potentially very severe consequences. The existence of previously well developed collateral circulation from the right coronary artery, may avoid the occurrence of extensive acute myocardial infarction with cardiogenic shock and death, which otherwise follows the acute occlusion. Once diagnosed, coronary artery bypass surgery is the first choice treatment, although coronary angioplasty can be performed as a bridge for surgery, or as an alternative, if surgery is not available or is not recommended, int he acute setting of myocardial infarction. Three of our patients underwent successful angioplasty, one electively and two as an emergency during acute myocardial infarction with cardiogenic shock, and five had coronary surgery, one after previous angioplasty due to restenosis. There are only three long term survivors. In our small experience, the severe hemodynamic deterioration after left main occlusion is the major risk factor for mortality, which can only be avoided by early angiographic diagnosis.