Influence of coronary thrombus on outcome of percutaneous coronary angioplasty in the current era (the Mayo Clinic experience)

Earlier studies documented an increased risk of percutaneous coronary intervention (PCI) in patients with angiographic evidence of thrombus. With newer antiplatelet agents and stents, it is not known whether thrombus is a risk factor after PCI. This study examines whether outcome of PCI in patients with thrombus has improved, and whether thrombus is associated with adverse outcome after PCI in the current era. This single-institution retrospective analysis of PCI in 7,184 patients was divided into 2 periods: group I, 1990 to 1995 (n = 3,640), and group II, 1996 to 1999 (n = 3,544). The groups were subdivided according to the presence or absence of angiographic thrombus before PCI. We compared the outcome of PCI for patients with and without thrombus in group II. A comparison was made in the 2 groups in patients with angiographic thrombus. Procedural success improved in group II compared with group I patients with thrombus (93% vs 88%, p <0.001). There was significant reduction in abrupt closure in the recent era in patients with thrombus (4% vs 7%, p = 0.01). In group II, procedural success remained lower in patients with (93% vs 96%) than without thrombus (p <0.001). After adjusting for the significant univariate characteristics of group II patients, thrombus remained an independent predictor of Q-wave infarction (odds ratio 3.78; 95% confidence interval [CI], 1.8 to 8.0; p <0.0013) and the composite end point of death, Q-wave infarction, and emergency bypass surgery (odds ratio 2.37; 95% CI 1.4 to 4.1; p = 0.002). There was a trend toward increased in-hospital death among patients with thrombus (odds ratio 2.06; 95% CI 0.9 to 4.8; p = 0.09). The 1-year outcome after successful PCI was similar for those with and without thrombus. Despite improvement in the outcome of patients with thrombus undergoing PCI in recent years, thrombus is still an independent predictor of adverse in-hospital outcomes after PCI.

Toward an understanding of violence: neurobehavioral aspects of unwarranted physical aggression: Aspen Neurobehavioral Conference consensus statement

OBJECTIVE

Violence is a global problem that poses a major challenge to individuals and society. This document is a consensus statement on neurobehavioral aspects of violence as one approach to its understanding and control.

BACKGROUND

This consensus group was convened under the auspices of the Aspen Neurobehavioral Conference, an annual consensus conference devoted to the understanding of issues related to mind and brain. The conference is supported by the Brain Injury Association and by individual philanthropic contributions. Participants were selected by conference organizers to represent leading opinion in neurology, neuropsychology, psychiatry, trauma surgery, nursing, evolutionary psychology, medical ethics, and law.

METHODS

A literature review of the role of the brain in violent behavior was conducted and combined with expert opinion from the group. The major goal was to survey this field so as to identify major areas of interest that could be targeted for further research. Additional review was secured from the other attendees at the Aspen Neurobehavioral Conference.

RESULTS

The group met in the spring of 1998 and 1999 for two 5-day sessions, between which individual assignments were carried out. The consensus statement was prepared after the second meeting, and agreement on the statement was reached by participants after final review of the document.

CONCLUSIONS

Violence can result from brain dysfunction, although social and evolutionary factors also contribute. Study of the neurobehavioral aspects of violence, particularly frontal lobe dysfunction, altered serotonin metabolism, and the influence of heredity, promises to lead to a deeper understanding of the causes and solution of this urgent problem.

Immediate and long-term outcome of intracoronary stent implantation for true bifurcation lesions

OBJECTIVES

The aim of this study was to evaluate the immediate and long-term outcome of intracoronary stent implantation for the treatment of coronary artery bifurcation lesions.

BACKGROUND

Balloon angioplasty of true coronary bifurcation lesions is associated with a lower success and higher complication rate than most other lesion types.

METHODS

We treated 131 patients with bifurcation lesions with > or =1 stent. Patients were divided into two groups; Group (Gp) 1 included 77 patients treated with a stent in one branch and percutaneous transluminal coronary angioplasty (PTCA) (with or without atherectomy) in the side branch, and Gp 2 included 54 patients who underwent stent deployment in both branches. The Gp 2 patients were subsequently divided into two subgroups depending on the technique of stent deployment. The Gp 2a included 19 patients who underwent Y-stenting, and Gp 2b included 33 patients who underwent T-stenting.

RESULTS

There were no significant differences between the groups in terms of age, gender, frequency of prior myocardial infarction (MI) or coronary artery bypass grafting (CABG), or vessels treated. Procedural success rates were excellent (89.5 to 97.4%). After one-year follow-up, no significant differences were seen in the frequency of major adverse events (death, MI, or repeat revascularization) between Gp 1 and Gp 2. Adverse cardiac events were higher with Y-stenting compared with T-stenting (86.3% vs. 30.4%, p = 0.004).

CONCLUSIONS

Stenting of bifurcation lesions can be achieved with a high success rate. However, stenting of both branches offers no advantage over stenting one branch and performing balloon angioplasty of the other branch.

Immediate and late outcomes after direct stent implantation without balloon predilation

OBJECTIVES

The aim of our study was to compare the in-hospital and long-term clinical outcomes of direct coronary stenting with balloon predilation followed by stent placement.

BACKGROUND

With improvement in stent designs, the practice of direct stenting without balloon predilation has become more widespread.

METHODS

We analyzed the Mayo Clinic Coronary Intervention data base between January 1, 1995 and March 5, 1999 and identified 777 patients who were treated with direct stenting (DS) and 3,176 patients treated with balloon angioplasty plus stenting (BA+S).

RESULTS

The procedural success rates between the DS and BA+S groups were not significantly different (96.3% vs. 96.4%). The ability to deliver the stent in a subgroup of patients who had DS was 95%, with 5% requiring crossover to predilation. Multivariate analysis showed no significant differences with respect to in-hospital death (odds ratio [OR] 0.9, 95% confidence interval [CI] 0.5 to 1.8), in-hospital myocardial infarction (OR 0.9, 95% CI 0.6 to 1.2) or revascularization (OR 0.7, 95% CI 0.4 to 1.5) in the DS compared with the BA+S group. Long-term outcomes were not significantly different between the DS and BA+S groups. The procedural duration was significantly shorter in the DS group, and there was a decreased utilization of contrast agent, balloons and wires.

CONCLUSIONS

The in-hospital and long-term clinical outcomes in patients undergoing a coronary intervention are equivalent when comparing stenting without balloon predilation with balloon angioplasty followed by stenting. Direct stenting is associated with decreased utilization of contrast agent and equipment and shorter procedure times. A randomized study should be performed to better determine the impact of this technique on short- and long-term procedural outcomes.

Interventional cardiology and intracoronary stents--a changing practice: approved vs. nonapproved indications

Our objective was to document change in stent usage in a single practice over time and to study "off-label" compared to Food and Drug Administration (FDA)-approved indications. Although only two intracoronary stents have been approved by the FDA, the relatively limited approved indications do not account for the dramatic increase in stent implantation. This increase has important implications for patient health care delivery. This study of stent usage in a single center over a 36-mo period included all patients treated with coronary stents at the Mayo Clinic from January 1993-December 1995, and evaluated the relative difference in frequency between "off-label" and FDA-approved indications for implantation. During the 36-mo period of study, 3,614 interventional procedures were done and one or more stents were placed in 25.4% of patients. The proportion of patients receiving stents increased throughout this time: during the first 6-mo period, stents were placed in 6.2% of procedures; during the last 6-mo period, stents were placed in 46.3% of procedures, an eightfold increase. During the final 6 mo, an unapproved device or an unapproved indication for an approved device constituted 59.4% of all stent procedures. In addition, use of the non-FDA-approved adjunctive treatment regimen without warfarin increased from 2.9% in the first 6-mo period of observation to 82.7% in the last 6 mo. The use of stents increased strikingly over a 36-mo period, from 6% to 46% of all procedures. The majority of implantations were performed either for an "off-label" unapproved indication or with an unapproved device.

Validation of a new UNIX-based quantitative coronary angiographic system for the measurement of coronary artery lesions

We describe a method of validation of computerized quantitative coronary arteriography and report the results of a new UNIX-based quantitative coronary arteriography software program developed for rapid on-line (digital) and off-line (digital or cinefilm) analysis. The UNIX operating system is widely available in computer systems using very fast processors and has excellent graphics capabilities. The system is potentially compatible with any cardiac digital x-ray system for on-line analysis and has been designed to incorporate an integrated database, have on-line and immediate recall capabilities, and provide digital access to all data. The accuracy (mean signed differences of the observed minus the true dimensions) and precision (pooled standard deviations of the measurements) of the program were determined x-ray vessel phantoms. Intra- and interobserver variabilities were assessed from in vivo studies during routine clinical coronary arteriography. Precision from the x-ray phantom studies (6-In. field of view) for digital images was 0.066 mm and for digitized cine images was 0.060 mm. Accuracy was 0.076 mm (overestimation) for digital images compared to 0.008 mm for digitized cine images. Diagnostic coronary catheters were also used for calibration; accuracy.varied according to size of catheter and whether or not they were filled with iodinated contrast. Intra- and interobserver variabilities were excellent and indicated that coronary lesion measurements were relatively user-independent. Thus, this easy to use and very fast UNIX based program appears to be robust with optimal accuracy and precision for clinical and research applications.

"Rescue" directional coronary atherectomy after unsuccessful percutaneous transluminal coronary angioplasty

OBJECTIVE

To evaluate the outcome in patients who underwent directional coronary atherectomy after unsuccessful balloon angioplasty.

DESIGN

We conducted a retrospective computerized data bank search of patients in whom unsuccessful balloon angioplasty and subsequent "rescue" coronary atherectomy had been performed at the Mayo Clinic between Nov. 1, 1988, and May 1, 1993.

MATERIAL AND METHODS

Among the 336 patients who underwent directional coronary atherectomy during the study period, in 16 the procedure was a rescue attempt. The mean age of these 16 study patients was 67 years. The following vessels were treated: left anterior descending coronary artery, six patients; right coronary artery, six; circumflex artery, two; and saphenous vein graft, two. Coronary angioplasty had failed because of dissection in eight patients, elastic recoil without evident dissection in seven, and recurrent thrombus without evident dissection in one.

RESULTS

After coronary atherectomy, the mean stenosis was 41% (in comparison with 90% before coronary angioplasty and 71% after coronary angioplasty). Both angiographic success (20% or more decrease in stenosis after tissue removal and a final stenosis of less than 50%) and clinical success (angiographic success without in-hospital Q-wave myocardial infarction, bypass operation, or death) were achieved in 10 patients. Adventitia was obtained in two patients, both of whom underwent atherectomy for elastic recoil. In six patients, a stenosis of more than 50% remained after atherectomy; one patient suffered a Q-wave myocardial infarction, and one underwent emergent coronary artery bypass grafting. No deaths occurred in the study group. During follow-up (mean, 22 +/- 19 months), one patient suffered a non-Q-wave myocardial infarction, and two others underwent elective coronary artery bypass grafting. Eleven patients were asymptomatic at last contact. Repeated angiography, done in five patients a mean of 3.4 +/- 3.1 months after the procedure, showed restenosis in three.

CONCLUSION

Rescue directional coronary atherectomy seems to be safe and effective in achieving angiographic and clinical successes in carefully selected patients after unsuccessful coronary angioplasty.

Immediate and long-term outcome after directional coronary atherectomy: analysis of gender differences

OBJECTIVE

To compare the short-term and long-term outcomes of directional coronary atherectomy in women and men.

DESIGN

We retrospectively analyzed 291 consecutive directional atherectomy procedures performed in 61 women and 230 men at the Mayo Clinic between October 1988 and November 1992.

MATERIAL AND METHODS

The baseline clinical and angiographic characteristics, including extent of coronary artery disease and left ventricular ejection fraction, were compared for the male and female patients, and the short-term and long-term complications associated with atherectomy were summarized on the basis of gender.

RESULTS

At baseline, women were older than men (67 +/- 12 versus 61 +/- 11 years; P = 0.001), and more women than men had class III or IV angina (90% versus 64%; P < 0.001); slightly more women than men had rest pain (64% versus 52%). Overall clinical success (improvement in luminal diameter of 40% or more and no death, Q-wave myocardial infarction, or emergency coronary bypass operation) was achieved in 89% of women and 95% of men (P = 0.054). In-hospital mortality was similar in women and men (1.6% and 1.7%, respectively), but acute myocardial infarction occurred more frequently in women than in men (4.9% versus 0.4%; P = 0.03). Significant peripheral vascular complications occurred in 6.6% of women versus 0.9% of men (P = 0.02). During long-term follow-up (mean, 2.9 years), survival and freedom from recurrent angina were similar among women and men.

CONCLUSION

Directional coronary atherectomy is associated with slightly lower success and a higher frequency of myocardial infarction among women than among men. The higher postprocedural rate of myocardial infarction among women may reflect their worse clinical status at time of initial assessment. Despite these observations, women and men seem to have comparable survival and freedom from recurrence of angina during extended follow-up.

Percutaneous excimer laser coronary angioplasty: results in the first consecutive 3,000 patients. The ELCA Investigators

OBJECTIVES

We report the comprehensive results of the first consecutive 3,000 patients treated in an excimer laser coronary angioplasty registry.

BACKGROUND

Excimer laser coronary angioplasty involves the use of a pulsed, 308-nm ultraviolet laser transmitted by optical fibers to reduce coronary stenoses. Preliminary reports have described safety and efficacy profiles in small numbers of patients.

METHODS

Patients were enrolled in a prospective, nonrandomized manner. The catheters used were 1.3, 1.6, 2.0, 2.2 and 2.4 mm in diameter, at energy densities up to 70 mJ/mm2. Procedures were performed by standard angioplasty technique with conventional guide catheters.

RESULTS

Seventy-five percent of patients were male, 68% were in Canadian Cardiovascular Society functional class III or IV and the cohort included 3,592 lesions. Procedural success (final stenosis < or = 50% without in-hospital Q wave myocardial infarction, coronary artery bypass surgery or death) was 90% and did not differ between the first 2,000 and the last 1,000 patients treated. There was no significant difference in success or complication rates with respect to lesion length, nor were there differences between selected complex and simple lesions. Complications included in-hospital bypass surgery (3.8%), Q wave myocardial infarction (2.1%) and death (0.5%). Coronary artery perforation occurred in 1.2% of patients (1% of lesions) but significantly decreased to 0.4% in the last 1,000 patients (0.3% of lesions). Angiographic dissection occurred in 13% of lesions, transient occlusion in 3.4% and sustained occlusion in 3.1%. Comprehensive lesion morphologic data collected in the latter portion of the study showed the procedure predominantly limited to American College of Cardiology-American Heart Association type B2 and C lesions, with no significant difference in short-term outcome between groups.

CONCLUSIONS

Excimer laser angioplasty can be safely and effectively applied, even in a variety of complex lesions not well suited for percutaneous transluminal coronary angioplasty. These types may include aorto-ostial, long lesions, total occlusions crossable with a wire, diffuse disease and vein grafts. Most recent data show a trend for the selection of predominantly complex lesions and a reduction in the incidence of perforation. This procedure may broaden the therapeutic window for the interventional treatment of selected complex coronary artery disease.

Coronary perforation after excimer laser coronary angioplasty: the Excimer Laser Coronary Angioplasty Registry experience

OBJECTIVES

This study assessed the frequency of perforation with excimer coronary angioplasty.

BACKGROUND

Coronary artery perforation after conventional percutaneous transluminal coronary angioplasty is extremely rare. Because laser coronary angioplasty involves actual tissue ablation, it has an increased potential for perforation.

METHODS

All patients in the Excimer Laser Coronary Angioplasty Registry were included in this prospective study. Those who had a perforation related to the procedure were compared with those who did not have this complication.

RESULTS

Of 2,759 consecutive patients in the Excimer Laser Coronary Angioplasty Registry, 36 (1.3%) had perforation. In these patients, the left anterior descending coronary artery was the most frequently treated vessel (53%). There were no differences in fiber sizes between patients with and those without perforation. Among the patients with perforation, 36.1% required coronary artery bypass surgery, 16.7% experienced an infarction and 5.6% had a fatal outcome. Among the patients without perforation, the rates were 3.1%, 3.8% and 0.6%, respectively. However, 41.7% of the patients with documented coronary artery perforation did not need coronary artery bypass surgery or experience myocardial infarction or death. No angiographic characteristics distinguished lesions with from those without perforation. The frequency of coronary artery perforation declined over time with increasing operator experience, from 1.6% in the first 1,888 patients to only 0.4% in the last 1,000 patients (p = 0.002).

CONCLUSIONS

With increasing operator experience, the rate of perforation with excimer laser coronary angioplasty has decreased. When perforation occurs, subsequent event rates increase.

Significance of anterior ST depression in inferior wall acute myocardial infarction

Early tomographic myocardial perfusion imaging with technetium-99m sestamibi was performed during inferior wall acute myocardial infarction to determine the relation between the amount and location of myocardium at risk and the presence or absence or anterior ST depression. The total size of the acute perfusion defect and its lateral and septal borders were measured in 29 consecutive patients who were admitted with > 30 minutes of chest pain and acute inferior ST elevation on their initial electrocardiogram. The 22 patients with anterior ST depression had significantly more left ventricular myocardium at risk than the 19 patients who did not have anterior ST depression (23 +/- 2% of the left ventricle vs 15 +/- 1%, p = 0.008). All 8 patients with > 25% of the left ventricle at risk had anterior ST depression. Patients with anterior ST depression had a significantly greater lateral extent of the acute perfusion defect (49 degrees +/- 8 degrees from the midinferior wall vs 23 degrees +/- 7 degrees, p = 0.002). There was no difference in the septal border of the perfusion defect between patients with and without anterior ST depression (-44 degrees +/- 4 degrees vs -46 degrees +/- 7 degrees, p = NS). No patient had a measurable anterior perfusion defect. Although there is considerable overlap between groups with and without anterior ST depression, anterior ST depression is a simple and readily available indicator of myocardium at risk in inferior wall acute myocardial infarction.

Chronic total obstruction and short-term outcome: the Excimer Laser Coronary Angioplasty Registry experience

Percutaneous transluminal coronary angioplasty for chronic total obstructions is associated with significantly decreased success rates in comparison with those for dilation of subtotal stenoses. Failure usually results from inability to cross the occlusive lesion with a guidewire, although it may result from inability to pass the balloon catheter after the guidewire has been passed. In the Excimer Laser Coronary Angioplasty Registry, 172 chronic total obstructions were treated in 162 patients (10.3% of the 1,569 patients entered). For chronic total obstructions, passage of a guidewire is a prerequisite for laser angioplasty. Once a guidewire crossed an occlusion, the overall laser success rate for treatment of chronic total obstructions was 83%; the extent of stenosis decreased from 100% to 55 +/- 26%. Success was independent of length of the occlusive lesion. In 74% of patients, adjunctive percutaneous transluminal coronary angioplasty was used after laser angioplasty. A final procedural success, defined as residual stenosis of less than 50% and no major complication (coronary artery bypass grafting, myocardial infarction, or death), was achieved in 90%. Major complications were infrequent; 1.2% of patients required coronary artery bypass grafting, and 1.9% had a Q-wave myocardial infarction. Only one death occurred. The use of laser angioplasty may be of particular value when chronic total obstructions can be crossed with a guidewire but not with a conventional balloon catheter or when the occlusion is confirmed to be extremely long.

Relation of deep arterial resection and coronary artery aneurysms after directional coronary atherectomy

OBJECTIVES

The aims of this study were to document the frequency of coronary artery aneurysm formation in patients undergoing directional coronary atherectomy and to determine the relation of such aneurysms to the depth of arterial resection.

BACKGROUND

Deep arterial injury is relatively frequent with the use of directional coronary atherectomy, but the potential for subsequent coronary artery aneurysm formation is unknown.

METHODS

Results in a consecutive series of 64 successfully treated patients (a total of 69 lesions; mean angiographic follow-up at 5 months) treated with directional coronary atherectomy were retrospectively analyzed with use of quantitative angiographic and histologic data.

RESULTS

Coronary aneurysms (ratio of dilated vessel segment to the adjacent reference segment > 1.2:1) occurred in seven patients (10%). The only significant clinical correlate of aneurysm formation was a relatively shorter duration of angina. There were no significant preprocedural angiographic predictors of aneurysms, although 6 (86%) of the 7 aneurysmal lesions arose from restenosis lesions compared with 30 (48%) of 62 lesions with no subsequent aneurysm development (p = 0.06). Histopathologic examination of 414 specimens from 68 treated lesions showed no significant difference in the occurrence of subintimal resection (media +/- adventitia) between those with and without subsequent aneurysm (29% vs. 22%). Media alone was found in 14% of specimens from lesions that later became aneurysmal versus 15% of those that did not; adventitial resection was found in 14% and 7% of specimens, respectively (p = 0.08), with relatively more adventitia per specimen from those with aneurysm (55% vs. 30% without aneurysm, p = 0.08).

CONCLUSIONS

Aneurysms occur relatively frequently after directional coronary atherectomy. Although there was no statistically significant correlation with the depth of arterial resection, the evidence from this study suggests that the role of adventitial resection in the occurrence of late aneurysm development should be explored further.

Results of directional atherectomy of primary atheromatous and restenosis lesions in coronary arteries and saphenous vein grafts

Directional coronary atherectomy (DCA) was performed in 158 patients over a 2-year period at the Mayo Clinic. Primary atheromatous lesions were treated in 92 patients (group 1) and restenosis lesions were treated in 66 (group 2). Technical success (recovery of tissue and greater than or equal to 40% luminal enlargement with a residual stenosis of less than 50%) was achieved in 152 lesions (92%); clinical success (technical success and no in-hospital death, Q-wave myocardial infarction or coronary bypass surgery) was achieved in 143 patients (91%). Adjunctive balloon angioplasty was used in 41 patients. DCA was successful less often in group 1 than in group 2 (86 vs 97%; p = 0.038). A major complication occurred in 7% of patients; in-hospital death, Q-wave myocardial infarction and emergency coronary bypass surgery occurred in 3, 1 and 4% of patients, respectively. Major complications were more frequent in group 1 than in group 2 (10 vs 1; p = 0.02). During a follow-up period of 14 +/- 8 months, no difference between the groups was found in the incidence of late death (4%), Q-wave myocardial infarction (1%), recurrent severe angina (29%), bypass surgery (15%) or repeat interventional procedure of the same vascular segment (24%). Vein graft and restenosis lesions tended to have greater success and fewer complications. Angiographic restenosis (increase of greater than or equal to 30% in stenosis severity by visual assessment) occurred in 62% of patients and 58% of lesions with successful DCA, and was similar in the 2 groups; a tendency toward higher restenosis rates was seen in patients with vein graft DCA.(ABSTRACT TRUNCATED AT 250 WORDS)

Fistulous pseudoaneurysm complicating surgical accessory pathway interruption for Wolff-Parkinson-White syndrome

Pseudoaneurysms of the left ventricle are unusual operative complications that have commonly been associated with replacement of the mitral valve. In this report, we describe a 31-year-old man who was referred to our institution because of atypical chest pain. He had previously undergone three operations for ablation of an accessory pathway because of Wolff-Parkinson-White syndrome. A pseudoaneurysm of the left ventricle was noted on transesophageal echocardiography, biplanar left ventriculography, and ultrafast cine computed tomography of the heart. Elective surgical repair was successful. Although rare, this case demonstrates an unusual but potentially serious complication of surgical treatment of Wolff-Parkinson-White syndrome.

Excimer laser coronary angioplasty: results in restenosis versus de novo coronary lesions. Excimer Laser Coronary Angioplasty Investigators

There is limited information regarding the use of excimer laser coronary angioplasty (ELCA) in patients with restenotic lesions. The purpose of this investigation was to compare the results of ELCA in patients with restenosis following prior PTCA with results obtained in de novo (no restenosis) patients. A retrospective review was obtained of all patients undergoing attempted ELCA at each of the 12 participating clinical investigative centers. There were 620 patients in the prior restenosis group and 949 in the de novo group. Both laser success (88% vs 78%) and procedural success (92% vs 88%) were higher in restenosis lesions compared with de novo lesions (P less than 0.001). Six-month follow-up was available in 40% of patients. Restenosis occurred in 49% of the prior restenosis group vs 44% of the de novo group (P nonsignificant) but death was more common in the de novo group (2.2 vs 0.4%, P = 0.01). ELCA can be performed with a high success rate in patients with restenosis following prior balloon angioplasty but recurrent restenosis following laser procedure remains a significant problem.

Percutaneous transluminal coronary angioplasty in patients with cardiogenic shock

In cardiogenic shock complicating acute myocardial infarction, percutaneous transluminal coronary angioplasty has been reported to significantly improve the modest survival benefits afforded by emergency surgical revascularization and thrombolytic therapy. The records of all patients who underwent angioplasty for acute myocardial infarction complicated by cardiogenic shock were retrospectively reviewed to determine whether coronary angioplasty improves survival. Of the 45 patients, 28 (group 1, 62%) had successful dilation of the infarct-related artery and 17 (group 2, 38%) had unsuccessful angioplasty. The groups were similar in extent of coronary artery disease, infarct location, incidence of multivessel disease and hemodynamic variables. The overall hospital survival rate was 56% (71% in group 1 and 29% in group 2). Group 1 patients had more left main coronary artery disease, and group 2 patients were older and had a higher incidence of prior myocardial infarction. Multivariate analysis showed that the survival advantage in patients with successful angioplasty was statistically significant (p = 0.014) when these factors were taken into account. At a mean follow-up interval of 2.3 years (range 1 month to 5.6 years), there were five deaths (four cardiac and one noncardiac), for a 2.3-year survival rate of 80% in patients surviving to hospital discharge. During the follow-up period, 36% of hospital survivors had repeat hospitalization for cardiac evaluation, 8% had myocardial infarction, 8% had coronary artery bypass surgery and 24% had angina.

Initial and long-term outcome of 354 patients after coronary balloon angioplasty of total coronary artery occlusions

BACKGROUND

Coronary balloon angioplasty of chronic total occlusions is associated with relatively low success rates and a high incidence of restenosis. Whether there is long-term benefit in performing angioplasty of these lesions is unknown. The purpose of the present report was to analyze the long-term outcome of a large series of patients undergoing this procedure.

METHODS AND RESULTS

A computerized database analysis of 354 consecutive patients (from 1979 to 1990) who underwent coronary angioplasty of a chronic total coronary occlusion was performed (mean age, 62.3 years). Initial technical success was achieved in 69%; in 66%, success was achieved without procedural death or need for coronary artery surgery. During hospitalization, six patients suffered myocardial infarction, nine required emergency bypass surgery, and nine patients died. During a mean follow-up period of 2.7 years, no difference was found in survival or freedom from myocardial infarction among 234 successfully dilated patients compared with 120 patients with a failed attempt. However, the use of coronary artery bypass surgery was significantly less after successful dilation (p less than 0.0001 versus failed attempt). No significant difference in the cumulative incidence of severe angina was observed between these two patient populations, with the majority remaining asymptomatic. Restenosis occurred in 59% of 69 patients who returned for follow-up angiography.

CONCLUSIONS

Successful recanalization is achieved in the majority of patients undergoing angioplasty of chronic total occlusions and reduces the need for coronary artery bypass surgery. However, no major impact on either survival or incidence of myocardial infarction was noted after successful recanalization when patients with surgery were included.

Outcome of noncardiac operations in patients with severe coronary artery disease successfully treated preoperatively with coronary angioplasty

The risk of perioperative myocardial infarction and death was evaluated in 50 patients (mean age, 68 years) with severe coronary artery disease who underwent a noncardiac operation after revascularization had been achieved by successful percutaneous transluminal coronary angioplasty. Before angioplasty, all patients were thought to be at high risk for perioperative complications on the basis of assessment of clinical variables and findings on specialized diagnostic tests. Of the 50 patients, 31 had Canadian Heart Association class III or IV angina or unstable angina. All patients who underwent functional testing had positive results. At catheterization, 38 patients (76%) had multivessel disease. The 50 patients underwent 54 noncardiac operations at a median of 9 days after angioplasty. The overall frequency of perioperative myocardial infarction was 5.6%, and the mortality was 1.9%. Two nonfatal non-Q-wave infarctions and one fatal Q-wave infarction occurred. In patients who have undergone successful angioplasty for severe coronary artery disease, the risk of major cardiac complications associated with a noncardiac surgical procedure is low.

Measurement of myocardium at risk by technetium-99m sestamibi: correlation with coronary angiography

Previous studies have shown that tomographic perfusion imaging with technetium-99m sestamibi (RP-30A) can accurately measure the myocardium at risk during acute myocardial infarction. The ability of coronary angiography to predict the wide variability in myocardium at risk was studied in 21 patients with their first acute myocardial infarction. In blinded fashion, two experienced angiographers provided an overall "best estimate" of the percent of left ventricular myocardium at risk considering multiple angiographic variables--infarct-related artery, location of stenosis (proximal or nonproximal), vessel diameter, length, territory and the number and size of proximal branches and collateral vessels. Many of these individual variables showed a significant association with myocardium at risk. The most important angiographic variable was the mean best estimate of the two angiographers (r = 0.89, p less than 0.0001). However, the SEE was large (8.6% of the left ventricle) and angiography significantly (p less than 0.002) overestimated myocardium at risk. When patients with an anterior or an inferior infarct were considered separately, the angiographic best estimate had a weaker correlation with myocardium at risk measured by technetium-99m sestamibi in patients in both groups (anterior infarction r = 0.65, p = 0.04; inferior infarction r = 0.65, p = 0.04. Seven patients with an inferior infarct and myocardium at risk ranging from 7% to 32% of the left ventricle had identical angiographic best estimates. Although angiographic estimates correlate closely with measurements of myocardium at risk in groups of patients, their ability to predict the myocardium at risk in individual patients is limited.

Interventional cardiology

Percutaneous transluminal coronary angioplasty remains the standard interventional catheterization approach for the treatment of coronary artery disease. Three broad groups of new therapeutic devices, including atherectomy or devices for mechanical debridement, lasers, and endoprostheses, and diagnostic devices such as ultrasonography and angioscopy are discussed in this article.

Primary angioplasty in myocardial infarction: assessment of improved myocardial perfusion with technetium-99m isonitrile

Technetium-99m-hexakis-2-methoxy-2-isobutyl-isonitrile (technetium-99m isonitrile) is a new radiopharmaceutical compound that reflects myocardial perfusion. Its kinetics, especially its lack of redistribution after intravenous administration, permits the assessment of changes in myocardial perfusion without delay of therapy. Tomographic images at rest were obtained immediately and 6 to 10 days later in 17 consecutive patients undergoing successful primary angioplasty during their first transmural myocardial infarction. Thirteen patients had anterior infarction. The initial (acute) defect size before angioplasty of 48 +/- 17% of the left ventricle decreased significantly (p less than 0.0001) to 29 +/- 19% on the late scans. There was no correlation between the time to therapy and the reduction in defect size. Twelve of the 17 patients, including 7 of the 11 patients treated after 4 h, demonstrated a definite reduction in the initial defect size. Eight patients with angiographically proved persistent coronary occlusion underwent a similar imaging sequence. The initial defect size in this group remained unchanged on the late scans (24 +/- 16% versus 26 +/- 18%, p = NS). Primary angioplasty is an effective approach toward salvaging myocardium; comparison with thrombolytic drug therapy must await the results of controlled clinical trials.

Restenosis after directional coronary atherectomy: differences between primary atheromatous and restenosis lesions and influence of subintimal tissue resection

Rates of restenosis were evaluated in 70 patients (74 lesions) after successful directional coronary atherectomy. The extent of vascular tissue resection was correlated with restenosis rates for coronary (n = 59) and vein bypass graft (n = 15) lesions. After 6 months, the overall restenosis rate was 50% (37 of 74 lesions); it was 42% (15 of 36 lesions) when intima alone was resected, 50% (7 of 14 lesions) when media was resected and 63% (15 of 24 lesions) when adventitia was resected. Subintimal tissue resection increased the restenosis rate for vein grafts (43% with intimal resection versus 100% with subintimal resection, p = 0.01) but not for coronary arteries (50% versus 48%). There was no overall difference in restenosis rates after atherectomy between primary lesions and restenosis lesions that occurred after balloon angioplasty (46% versus 54%). Among postballoon angioplasty restenosis lesions, a higher rate of restenosis after atherectomy was found with subintimal than with intimal resection (78% versus 32%, p = 0.01). Tissues from patients undergoing a second atherectomy for restenosis after initial atherectomy (n = 8) demonstrated neointimal hyperplasia that appeared histologically identical to restenotic tissue developing after balloon angioplasty (n = 37). These data suggest that the cellular response to directional coronary atherectomy is characterized by neointimal proliferation similar to that which may develop after balloon angioplasty. The extent of fibrous hyperplasia appears to be related to the depth of tissue resection in vein graft lesions and coronary artery restenosis lesions that occur after balloon angioplasty but not in primary atheromatous coronary artery lesions.

Emergency "rescue" percutaneous transluminal coronary angioplasty after failed thrombolysis with streptokinase. Early and late results

Although thrombolytic therapy has been a major advance in the treatment of acute myocardial infarction, in at least 25% of patients the artery remains occluded after administration. In these patients, the strategy of "rescue" or "salvage" angioplasty is frequently used although follow-up data are limited. Sixty-three patients underwent percutaneous transluminal coronary angioplasty (PTCA) after thrombolytic therapy for acute myocardial infarction. The decision to proceed with PTCA was based on physician preference and not a specific research protocol. In 34 of these selected patients, PTCA was performed as a rescue procedure because the infarct-related artery remained occluded (group 1); in 29 of these patients, it was performed to treat a severe but subtotal residual stenosis (group 2). PTCA successfully restored patency in 71% of group 1 and in 90% of group 2. Group 1 patients had a significantly worse baseline ejection fraction than did those in group 2 (47 +/- 13% vs. 58 +/- 13%, p = 0.0015). Group 1 patients also had a significantly worse predismissal ejection fraction (36 +/- 13% vs. 50 +/- 14%, p = 0.0004). During initial hospitalization, 14 (22%) patients underwent coronary bypass surgery. In-hospital mortality was low in each group (3% in group 1 and 0% in group 2). During a mean follow-up of 4 years, 89% of group 1 patients remained alive as compared with 97% of group 2 patients. This excellent 4-year survival rate, despite the depressed predismissal ejection fraction in patients undergoing rescue PTCA, raises the issue of whether acute reperfusion has a beneficial effect aside from any impact on myocardial salvage and preservation of left ventricular function.

Doppler evaluation of results of percutaneous aortic balloon valvuloplasty in calcific aortic stenosis

To evaluate the short-term results of percutaneous aortic balloon valvuloplasty, 55 consecutive elderly patients with symptomatic, severe aortic stenosis who were at high risk for surgical intervention underwent the procedure, with follow-up by clinical evaluation and Doppler echocardiography. Over a mean follow-up of 6.2 months, there were three early deaths (less than 30 days) and eight late deaths. Nine patients underwent subsequent aortic valve surgery, and four had repeat balloon valvuloplasty. Doppler echocardiography revealed a reduction in aortic valve mean gradient from 48 +/- 18 to 33 +/- 12 mm Hg after the procedure (p less than 0.0001) but a return to 46 +/- 16 mm Hg at follow-up (p less than 0.05). The aortic valve area increased from 0.54 +/- 0.15 to 0.85 +/- 0.23 cm2 after the procedure (p less than 0.0001), but there was a significant decrease to 0.67 +/- 0.19 cm2 at follow-up (p less than 0.05). Of patients free of aortic valve operation or death after 30 days after the procedure, 76% were severely symptomatic before the procedure as compared with 38% at follow-up. In patients undergoing percutaneous aortic balloon valvuloplasty, there is a continued high short-term mortality and a significant incidence of restenosis over short-term follow-up. Nonetheless, a subset of patients do experience sustained clinical improvement from this procedure.

Results of percutaneous transluminal coronary angioplasty for unstable angina pectoris in patients 70 years of age and older

Between November 1980 and November 1985, 54 patients ages greater than or equal to 70 years underwent percutaneous transluminal coronary angioplasty for unstable angina, defined as recent-onset (less than 1 month) angina, new onset of rest angina (greater than or equal to 2 episodes) or accelerating class III or IV angina. In these 20 men and 34 women, disease was 1-vessel in 34 (63%) and multivessel in 20 (37%). The mean (+/- standard deviation) ejection fraction was 0.62 +/- 0.12. Angioplasty was successful in 43 patients (80%). In the 11 unsuccessful cases, emergency coronary artery bypass grafting for acute occlusion was performed in 3 and elective coronary artery bypass surgery in 8. There were no deaths. Two patients (4%) sustained Q-wave myocardial infarctions. The mean duration of follow-up for the total group was 37 months (6 to 73 months). Of the 43 patients with successful dilation, 4 died, 1 had an non-Q-wave myocardial infarction and 8 had symptomatic restenosis (4 underwent successful repeat angioplasty, 1 had repeat percutaneous transluminal coronary angioplasty and then bypass surgery, 1 had repeat bypass surgery alone and 2 had medical therapy). At last follow-up, 3 patients had stable class III or IV angina and 31 patients (72%) were angina-free.

A challenge to examine the meaning of living and dying

The case of Paul Brophy, decided by a four-to-three vote of the Supreme Judicial Court of Massachusetts, focused on the patient's right to terminate artificial nutrition and hydration. According to the majority opinion, artificial feeding is an "intrusive" procedure that one should be able to refuse without being accused of committing suicide. The court based its reasoning on the right to privacy and, in relation to that right, the state's interests in preserving life, protecting innocent third parties, preventing suicide, and maintaining the medical profession's ethical integrity. The majority could have been more persuasive, however, if it had considered Catholic moral tradition in developing its argument, especially the importance of judging a treatment's outcome and burden in relation to the individual patient's life. The Brophy opinion probably will leave many people dissatisfied because it fails to explore the values of the parties involved and the meaning of Catholic teaching. It should serve as a challenge, however, to the Catholic community to more fully articulate for a technologically oriented culture the meaning of living and dying.

Coronary artery thrombus as a risk factor for acute vessel occlusion during percutaneous transluminal coronary angioplasty: improving results

Early experience with percutaneous transluminal coronary angioplasty (from October 1979 to March 1983 inclusive) showed that pre-existing coronary artery thrombus was associated with a significant increase in the incidence of acute coronary occlusion during angioplasty. Acute occlusion occurred in 11 (73%) of 15 patients with pre-existing thrombus compared with 18 (8%) of 223 patients without thrombus. The effect of improved technology (steerable guiding systems) and altered dilatation strategy (full intravenous heparinisation for 24 hours after the procedure and more intensive use of antiplatelet medications) was studied by review of angiograms from 297 consecutive patients without evidence of acute myocardial infarction who underwent angioplasty from April 1983 to March 1985 inclusive. Coronary artery thrombus was present in 34 (11%) patients, eight (24%) of whom had complete occlusion during or immediately after the procedure compared with 34 (13%) of 263 patients without thrombus. Patients with pre-existing coronary artery thrombus continue to be at greater risk of complete occlusion than patients without thrombus, but this risk has declined significantly since the modification of the angioplasty procedure.

Genetic control of susceptibility to mite-associated ulcerative dermatitis

Variable susceptibility to mite-associated ulcerative dermatitis (MAUD) attributable to Myobia musculi infestation was studied in breeding stocks of sixteen inbred strains of mice. Statistical evaluation of 41 occurrences of lesion among 1,517 mice of the various strains indicated that significant differences in the frequency of MAUD were associated with differences in genetic background and in the H-2 type. These findings suggest that the occurrence of an ulcerative skin lesion in inbred mice exposed to M. musculi is controlled by at least two genes. Lesion susceptibility appears to be profoundly affected by a non-H-2 linked gene or gene combination shared by all C57Bl background strains. In addition, a major influence is exerted by one or more genes within the H-2 complex.

Resistance of cats to the diabetogenic effect of alloxan

Experimental diabetes mellitus can be induced chemically in many species of animals with streptozotocin or alloxan. However, the cat is known to be resistant to the diabetogenic effect of streptozotocin. The purpose of this study was to find the optimal dose and rate of injection of alloxan to consistently produce hyperglycemia (blood sugar levels greater than 300 mg/dl) in cats. Alloxan was administered to 22 cats at various concentrations (50, 100 and 150 mg/kg) and different rates of injection (0.5, 1.0 and 1.5 ml/min). No hyperglycemic effect was observed at any of the concentrations or different rates of injection. Cats receiving high concentrations and/or high rates of injection of alloxan died due to kidney damage. The results of this study suggest that the cat is resistant to the diabetogenic effect of alloxan, but is susceptible to its toxic side effects.

Angioplasty for aortocoronary bypass graft stenosis

During the period November 1979 to October 1984, 19 patients at our institution underwent balloon angioplasty of partial or complete obstruction of aortocoronary artery saphenous vein bypass grafts. The procedures were performed a mean of 38 months after a coronary bypass operation to relieve recurrent angina of at least class 2 in the Canadian Cardiovascular Association functional classification. Graft angioplasty was successful in 16 of the 19 patients, and the location of the lesion (in the origin, body, or distal insertion of the graft) did not seem to be an important factor in achieving a successful result. At a mean follow-up interval of 20 months (range, 1 to 40 months), 14 patients had symptomatic improvement. Two patients required late repeat operation and four had repeat angioplasty because of restenosis. Our experience supports the use of balloon angioplasty in selected patients with bypass graft stenosis, but restenosis remains a substantial problem.

Percutaneous transluminal coronary angioplasty, alone or in combination with streptokinase therapy, during acute myocardial infarction

The treatment strategy in 66 consecutive patients who underwent invasive therapy for acute myocardial infarction was analyzed, and specific attention was focused on the role of percutaneous transluminal coronary angioplasty. The following four treatment regimens were used: angioplasty alone (11 patients), angioplasty followed immediately by administration of streptokinase (15), streptokinase therapy alone (11), and streptokinase therapy followed by angioplasty (29). Reperfusion was achieved in 91%, 80%, 82%, and 72% of these subgroups, respectively. Angioplasty was particularly helpful in patients with severe residual stenoses after intracoronary administration of streptokinase and in patients in whom streptokinase therapy failed to reopen the occluded artery. Angioplasty further reduced the residual stenosis in 11 of 15 patients (73%) with successful thrombolysis, and it restored blood flow in 10 of 14 patients (71%) in whom thrombolysis had failed to do so. The incidence of reinfarction after therapy was similar in all four treatment groups. Patients in whom angioplasty was used either alone or in combination with streptokinase therapy had a significantly decreased incidence of subsequent revascularization (less than 30% compared with 82%). Angioplasty is of considerable value in patients undergoing invasive therapy for acute infarction. In some patients, it may be used as the only treatment; in others, it may be used to treat severe residual stenosis after initial streptokinase therapy. Finally, angioplasty achieves reperfusion in most patients in whom streptokinase therapy has failed.

Continuous-wave Doppler echocardiographic assessment of severity of calcific aortic stenosis: a simultaneous Doppler-catheter correlative study in 100 adult patients

Studies of the correlation of aortic valve gradient determined by continuous-wave Doppler echocardiography and that determined at catheterization have, to date, involved young patients and nonsimultaneous measurements. We therefore obtained simultaneous Doppler echocardiographic and catheter measurements of pressure gradient in 100 consecutive adults (mean age 69, range 50 to 89 years). In 63 patients pressure measurements were obtained with dual-catheter techniques and in 37 they were obtained by withdrawal of the catheter from the left ventricle to the ascending aorta. Forty-six of these patients also underwent an outpatient Doppler study 7 days or less before catheterization. The simultaneous pressure waveforms and Doppler spectral velocity profiles were digitized at 10 msec intervals and maximum, mean, and instantaneous gradients (mm Hg) were derived for each. The correlation between the Doppler-determined gradient and the simultaneously measured maximum catheter gradient was r = .92 (SEE = 15 mm Hg), that between the Doppler-determined and mean catheter gradient was r = .93 (SEE = 10 mm Hg), and that between the Doppler and peak-to-peak catheter gradient was r = .91 (SEE = 14). The correlation between the nonsimultaneously Doppler-determined gradient and the maximum gradient measured by catheter was not as strong (r = .79, SEE = 24). The continuous-wave Doppler echocardiographic velocity profile represents the instantaneous transaortic pressure gradient throughout the cardiac cycle. The best correlation with continuous-wave Doppler-determined gradient was obtained with maximum and mean gradients measured by catheter. Continuous-wave Doppler echocardiography can be used to reliably predict the pressure gradient in adults with calcific aortic stenosis.

Follow-up clinical results in patients undergoing percutaneous transluminal coronary angioplasty

Complete follow-up data were obtained from 229 consecutive patients who underwent percutaneous transluminal coronary angioplasty (PTCA) between 1979 and 1982 (mean follow-up 14 months, range 6 to 37). Single-vessel disease was present in 143 and multivessel disease in 86. PTCA was successful in 153 patients (67%). Failure was followed initially by bypass surgery in 59 and by continued medical therapy in 17. After successful PTCA, 90% of patients were improved subjectively and 74% were asymptomatic at follow-up. After unsuccessful PTCA but prompt bypass, 90% were improved subjectively and 85% were asymptomatic. Among the 229 patients, 39 (17%) required an additional intervention because of angina during follow-up; 15 of these had repeat PTCA and 18 had bypass surgery. Among patients with successful PTCA, revascularization was complete in 77% and partial in 23%. The completeness of revascularization with PTCA had a significant impact on follow-up. The follow-up data of patients with successful single-vessel PTCA and of those with multivessel disease with complete revascularization were similar. When the patients with complete revascularization were compared with those with multivessel disease but incomplete revascularization, the follow-up data were characterized by a higher incidence of angina or need for bypass surgery in the latter group (63%) than in the former group (29%); those with incomplete revascularization also had a significantly reduced event-free survival.

Intracoronary thrombus: role in coronary occlusion complicating percutaneous transluminal coronary angioplasty

Angiograms from 238 consecutive patients who underwent percutaneous transluminal coronary angioplasty at the Mayo Clinic were reviewed to determine the presence of intracoronary thrombus before dilation. Patients with previously occluded vessels and those receiving streptokinase therapy were excluded. Intracoronary thrombus before dilation was present in 15 patients (6%); complete occlusion occurred in 11 (73%) of these during or immediately after dilation. None of these patients had angiographic evidence of major intimal dissection. In contrast, among the 223 patients in whom no intracoronary thrombus was present before dilation, complete occlusion occurred in 18 (8%) and in 12 was associated with major intimal dissection. The difference between the complete occlusion rates for patients with and without prior intracoronary thrombus was highly significant (73 versus 8%, respectively, p less than 0.001). Therefore, the presence of intracoronary thrombus identifies a group of patients who are at increased risk of developing complete occlusion during or after attempted coronary artery dilation.

Estimation of the effects of angioplasty on coronary stenosis using quantitative video angiography

In this study, we compared stenosis severity by quantitative coronary angiography from video and cine images with visual estimation in 14 patients who underwent PTCA. Both cine and video analysis demonstrated a change from 65.2 +/- 2.5 to 36.5 +/- 3.1% diameter stenosis following PTCA, whereas visual estimation (average of three observers) showed improvement from 89.9 +/- 1.7 to 36.0 +/- 3.2%. Percent area stenosis from quantitative angiography showed improvement from 87.9 +/- 1.8 to 56.4 +/- 5.8. These data indicate that visual assessment overestimated percent diameter of severe lesions. To determine if video analysis could provide rapid quantitative assessment of PTCA results, we compared percent diameter and percent area stenosis by video with cine (diameter: correlation coefficient, 0.82; slope, 0.79; area: correlation coefficient, 0.86; slope, 0.83). These results indicate that video-based measurements are not different from cine-derived measurements. Quantitative coronary angiography provides an accurate estimate of changes produced by PTCA and can be performed rapidly and accurately on video images, thus making results available during the PTCA procedure.

Yersinia enterocolitica infection in breeding colonies of ruffed lemurs

Two outbreaks of yersiniosis caused by Yersinia enterocolitica occurred in breeding colonies of red ruffed lemurs (Varecia variegata rubra) and black and white ruffed lemurs (Varecia variegata variegata) housed in outdoor enclosures during the winter breeding season and spring birth season, respectively. Seven of 11 animals at risk in the combined outbreaks became ill, and 3 died of acute to chronic infection. Clinical signs included anorexia, lethargy, diarrhea, abdominal pain, and hyperpyrexia. Necropsy findings included ulcerative enterocolitis and multifocal necrosis and abscess formation in mesenteric lymph nodes, liver, spleen, kidneys, and lungs. Histologically, lesions were characterized by necrotizing inflammation containing masses of basophilic bacteria. Yersinia enterocolitica serotype 0:2 was isolated from lesions. Neomycin sulfate given orally and chloramphenicol given intramuscularly were effective in treatment early in the course of the disease or in mild cases. In severe cases, lemurs did not respond to antibiotic and fluid therapy. Exposure to soil contaminated with infected rodent feces, stress, and behavioral factors in the ruffed lemur species are believed to have precipitated the infection.

Angioplasty in total coronary artery occlusion

Percutaneous transluminal coronary angioplasty was attempted without streptokinase in 24 patients with total coronary artery occlusion but without acute transmural myocardial infarction. The maximal duration of occlusion was estimated to be 1 week or less in 10 patients, more than 1 to 4 weeks in 6, more than 4 to 12 weeks in 3 and more than 12 weeks in 5. Dilation of the occluded artery was attempted in the left anterior descending coronary artery in 17 patients, in the right coronary artery in 4 and in the circumflex coronary artery in 3. Angioplasty was successful in 13 patients (54%): left anterior descending coronary artery in 59%, right coronary artery in 50% and circumflex coronary artery in 33%. In patients with successful dilation, there was a mean decrease in coronary artery stenosis from 100 to 23%. In the 19 patients whose occlusion was estimated to be of 12 weeks' duration or less, angioplasty was successful in 68%. In the five patients whose occlusion was estimated to be of more than 12 weeks' duration, dilation was not successful in any (p = 0.006). It is concluded that in selected patients with symptomatic coronary artery disease and recent coronary artery occlusion without associated acute myocardial infarction, percutaneous transluminal coronary angioplasty alone may be effective in restoring patency.

Balloon angioplasty in multivessel coronary artery disease

Coronary angioplasty with use of the balloon catheter was initially performed only in patients with single-vessel coronary artery disease. Most symptomatic patients with coronary artery disease who require revascularization for control of their symptoms, however, have stenoses in more than one major coronary artery. Therefore, we have evaluated the results of balloon angioplasty in patients with multivessel disease. Of 261 patients who underwent percutaneous transluminal coronary angioplasty at our institution up to February 1983, 100 had multivessel disease. Of these 100 patients, 72 had an initially successful procedure, defined as successful dilation of one or more major coronary arteries without significant complication. Of the remaining 28 patients, 25 underwent coronary artery bypass grafting (6 on an urgent basis for coronary occlusion). No deaths occurred. In selected patients with multivessel disease, coronary angioplasty is associated with low morbidity and mortality and might be an excellent alternative to coronary artery bypass grafting when medical treatment fails. Percutaneous transluminal coronary angioplasty merits the critical comparison with standard therapy that can be achieved only in a properly designed clinical trial.

Facial hair barbering in rats

Facial alopecia was observed in three of four adult, female, Fischer 344 rats sharing the same cage for 2 months. Alopecia was characterized by irregular areas of hair loss between the eyes, which occasionally extended below the eyes and between the ears. These areas were nonpruritic and were not associated with dermatophytes, pathogenic skin bacteria, or ectoparasites. When the unaffected rat was removed and allowed to cohabit with new cagemates, facial alopecia became apparent in those animals within 6 days, and the hair of the original cagemates grew back within 3 weeks. The alopecia was caused by hair barbering by a dominant female rat.

Nasal dermatitis in the Mongolian gerbil

The prevalence of nasal dermatitis in two breeding colonies of Mongolian gerbils was determined; 56 of 302 (18.5%) were affected in Colony A, and 2 of 54 (3.7%) were affected in Colony B. The presence of nasal lesions did not correlate with sex, tail barbering, or epilepsy. There was a positive correlation between presence of nasal lesions and forepaw dermatitis, periocular alopecia, and protrusion of the nictitating membrane. Lesions were most common in the superior labial and lateral nasal regions. Histopathologic changes in the nasal area included acanthosis, mild hyperkeratosis, and inflammation of the dermis. Isolates of beta-hemolytic Staphylococcus aureus of several phage types were cultured from the nasal area of affected and nonaffected animals in both colonies. Staphylococcus saprophyticus isolates were associated with the development of early nasal lesions.

Angiographic changes produced by percutaneous transluminal coronary angioplasty

Percutaneous transluminal coronary angioplasty (PTCA) is being used with increasing frequency in the treatment of patients with symptomatic coronary artery disease. Balloon inflation results in diverse angiographic findings, reflecting the great variety of anatomic and pathologic changes produced. The long-term effects of inflation on the underlying atherosclerotic lesion and the clinical outcome are unknown but may depend in part on the anatomic changes caused by the dilatation itself. To facilitate communication and evaluation of the results of PTCA, a classification of the angiographic findings and their potential mechanisms is presented. Recognition and analysis of these angiographic findings may be helpful in evaluating the long-term outcome of patients undergoing PTCA.

Nephroblastoma with associated aortic rupture in a rat

A nephroblastoma was diagnosed in a 6-month-old, male rat which died unexpectedly. The right kidney was replaced by a large, white, irregularly shaped mass. Microscopically, the mass consisted of an embryonic blastema showing epithelial differentiation into immature tubules and glomeruloid structures. An aortic aneurysm and aortic rupture were present within the thoracic cavity. It was suspected that the aortic rupture was secondary to hypertension mediated through the renin-angiotensin system.