Thomas W. Nygaard

Complications of femoral artery closure devices.

We have examined our prospectively collected experience with femoral artery closure devices. Vasoseal (n = 937), Angioseal (N‐742), and Techstar (n = 1001) were utilized consecutively in our laboratory for diagnostic and interventional femoral artery closures. Complications were compared to a similar number of closures with manual compression (MC; n = 1019) before closure devices were utilized. The incidence of surgical repair, acute femoral closure, transfusion due to groin complications, readmission for groin complications, infection, and total complications were examined. We found that the Vasoseal and Angioseal devices were associated with higher rates of total complications than manual compression. The Techstar and manual compression had similar total complication rates. Acute femoral artery occlusion was a potentially serious complication with the Angioseal device. Groin infection occurred with each of the closure devices but not with manual compression. Cathet Cardiovasc Intervent 2001;52:3–7.

Effects of successful intravenous reperfusion therapy on regional myocardial function and geometry in humans: a tomographic assessment using two-dimensional echocardiography

This study tested the hypothesis that reperfusion therapy might provide benefit at two levels: 1) by arresting infarct migration at the endocardial level, such that partial or complete recovery of regional function occurs; and 2) if the former is not achieved, by preventing complete or near complete transmural migration and subsequent infarct expansion. To test this hypothesis, 24 patients who received intravenous streptokinase therapy within 4 h of chest pain were studied prospectively. All patients underwent two-dimensional echocardiography at the time of admission and 1, 2, 3 and 10 days later. The patients also underwent coronary angiography 2 h after completion of streptokinase therapy. Although 18 (75%) of the 24 patients had a patent infarct-related artery, only 8 (45%) of the 18 patients with this finding showed improvement in regional function. Improvement was not evident until 3 to 10 days after streptokinase therapy. In addition to the presence of an open infarct-related artery, the interval between chest pain and onset of streptokinase therapy (2.5 +/- 0.5 versus 3.2 +/- 0.7 h, p = 0.02) differed significantly between patients who did or did not show improved regional function. Of the 15 of 16 patients with no improvement in regional function, 4 showed infarct expansion, and all had a closed infarct-related artery compared with only 2 of the 11 not showing expansion (p = 0.01). In conclusion, intravenous streptokinase given within 4 h of chest pain results in improvement in regional function in about 33% of the patients, presumably by arresting the infarction within the endocardium.(ABSTRACT TRUNCATED AT 250 WORDS)

Prevalence of high-risk thallium-201 scintigraphic findings in left main coronary artery stenosis: Comparison with patients with multiple- and single-vessel coronary artery disease

To determine the prevalence of high-risk thallium-201 (Tl-201) scintigraphic findings in patients with left main (LM) coronary artery disease (CAD), quantitative exercise Tl-201 scintigrams were analyzed in 295 consecutive patients with angiographic (greater than or equal to 50% stenosis) CAD, of which 43 (14%) had greater than or equal to 50% LM stenosis. A high-risk scintigram was defined as one that demonstrated (1) a LMCAD scintigraphic pattern (greater than or equal to 25% homogeneous decrease in Tl-201 activity in the middle and upper septal and posterolateral walls on the 45 degree left anterior oblique projection); (2) abnormal Tl-201 uptake or washout in multiple vascular scan segments indicative of multivessel disease; and (3) increased lung Tl-201 uptake on the initial anterior projection image. Of the 43 patients with LMCAD, 41 (95%) had an abnormal scintigram. Thirty-three (77%) had 1 or more high-risk scintigraphic findings, including 29 (67%) with a multivessel CAD scan pattern, of which 6 (14%) demonstrated a typical LMCAD pattern; and 18 (42%) with abnormal lung Tl-201 uptake. The prevalence of a high-risk scintigram in patients with LMCAD was significantly greater than that in 53 patients with 3-vessel disease (58%) (p = 0.05), 99 patients with 2-vessel disease (60%) (p = 0.04) and 100 patients with 1-vessel disease (41%) (p less than 0.0001).(ABSTRACT TRUNCATED AT 250 WORDS)

Acute non-Q wave myocardial infarction associated with early ST segment elevation: Evidence for spontaneous coronary reperfusion and implications for thrombolytic trials

The clinical significance of early ST segment elevation in patients with non-Q wave infarction is unknown. Therefore, 150 consecutive patients with creatine kinase isoenzyme-confirmed acute uncomplicated myocardial infarction who had ST segment elevation of 1 mm or more in at least two contiguous leads on the admission electrocardiogram were analyzed. None received thrombolytic therapy or acute coronary angioplasty. Predischarge angiography, radionuclide ventriculography and exercise thallium-201 scintigraphy were performed 10 +/- 3 days after myocardial infarction. Based on serial electrocardiograms (on days 1, 2, 3 and 10), all 150 infarcts were classified as Q wave (n = 115 [77%]) or non-Q wave (n = 35 [23%]). Although patients with Q wave infarction exhibited greater ST elevation, the amount observed in the non-Q wave group was appreciable, as reflected by the number of leads with ST elevation (3.8 +/- 1.8 versus 3.1 +/- 1.2, p = 0.007) and the sum of the ST elevation (9.6 +/- 7.4 versus 6.2 +/- 6.2 mm, p = 0.016). When compared with the Q wave group, patients with non-Q wave infarction had a shorter time to peak creatine kinase (23.0 +/- 9.1 versus 15.8 +/- 7.9 hours, p = 0.0001), a higher infarct vessel patency rate (24 versus 57%, p = 0.001), lower peak creatine kinase values based on 4 hour sampling (1,372 +/- 964 versus 664 +/- 924 IU/liter, p = 0.0002) and a higher left ventricular ejection fraction (46 +/- 12% versus 54 +/- 9%, p = 0.0003).(ABSTRACT TRUNCATED AT 250 WORDS)

Acute myocardial infarction associated with single vessel coronary artery disease: An analysis of clinical outcome and the prognostic importance of vessel patency and residual ischemie myocardium☆

Abstract The long-term outcome and the significance of residual ischemie myocardium, as assessed by predischarge exercise thallium scintigraphy and vessel patency, were studied in 97 patients with single vessel coronary artery disease by angiography 12 ± 4 days after uncomplicated myocardial infarction. During a mean follow-up period of 39 ± 17 months, ηρ patients died, 6 (6%) had a recurrent nonfatal infarction and 25 (26%) experienced rapidly progressive angina requiring hospitalization. Although neither exercise-induced angina nor ST segment depression was predictive of a recurrent cardiac event, the mean number of infarct zone scan segments showing thallium redistribution (1.0 ± 1.0 versus 0.5 ± 0.8, p = 0.01) and the percent of patients with infarct zone redistribution (61 versus 39%, p = 0.05) were greater in those patients who experienced a late ischemie event. Kaplan-Meier analysis demonstrated a tower event-free survival rate in patients with redistribution (n = 45) than in those without redistribution (n = 52) (p = 0.019). Although no patient received immediate ihrombolytic therapy, the infarct-related vessel was angiographically patent in 40 patients (41%). Vessel patency did not influence event-free survival, although a patent vessel, as compared with an occluded vessel, was associated with a greater prevalence of nun-Q wave infarction (58 versus 21%. p In summary, uncomplicated myocardial infarction in patients with single vessel coronary artery disease is associated with a very low incidence of subsequent death and reinfarction. The presence of infarct zone thallium redistribution), compared with its absence, is predictive of a higher cardiac eyent rate. These data should be considered when recommending prophylactic percutaneous transluminal angioplasty after uncomplicated myocardial infarction in asymptomatic patients with single vessel coronary disease. On the basis of these results, future randomized trials designed to evaluate the therapeutic efficacy of revascuiarization in asymptomatic postinfarction patients with single vessel disease should limit enrollment to those patients with residual ischemia located within the infarct zone.

A prospective clinical, scintigraphic, angiographic and functional evaluation of patients after inferior myocardial infarction with and without right ventricular dysfunction

To elucidate the functional and prognostic significance of right ventricular dysfunction after acute inferior wall myocardial infarction, 74 consecutive patients with inferior infarction were prospectively evaluated with gated equilibrium blood pool imaging at rest, submaximal exercise thallium-201 scintigraphy and coronary angiography before hospital discharge. In addition, symptom-limited stress thallium-201 scintigraphy was performed in 61 patients at 3 months, and all patients were followed up clinically for 23 +/- 15 months. Utilizing predetermined radionuclide angiographic criteria, 47 patients (Group I) had normal right ventricular function, 12 patients (Group II) had mild to moderate dysfunction and 15 patients (Group III) had severe right ventricular dysfunction. There were no significant differences among the groups with regard to age, history of prior myocardial infarction, peak creatine kinase values, maximal Killip functional class, number or type of in-hospital complications, left ventricular ejection fraction, prevalence of multivessel disease or the distribution and severity of disease affecting the infarct-related vessel. Exercise tolerance as assessed by treadmill time, blood pressure-heart rate product and peak work load in METS was comparable among the three groups, both before hospital discharge and at 3 month follow-up. No differences in indicators of exercise-induced ischemia were noted among the groups, including the prevalence of redistribution thallium-201 defects, ST segment depression or symptoms of chest pain. Finally, cardiac mortality, reinfarction rate and the incidence of medically refractory angina pectoris were similar in the three groups. Thus, right ventricular dysfunction after acute inferior wall myocardial infarction does not appear to limit exercise tolerance or identify a subgroup of patients at higher risk for recurrent cardiac events.

Quantitative exercise thallium-201 scintigraphy for predicting angina recurrence after percutaneous transluminal coronary angioplasty☆

The aim of this prospective study was to determine the value of quantitative exercise thallium-201 scintigraphy for predicting short-term outcome in patients after percutaneous transluminal coronary angioplasty (PTCA). Quantitative exercise thallium-201 scintigraphy was performed 2.2 +/- 1.2 weeks after successful PTCA in 68 asymptomatic patients, 64 (94%) of whom had class III or IV angina before the procedure. Clinical follow-up was obtained in all patients at a mean of 10 +/- 2 months and all were followed for at least 6 months; 45 patients (66%) remained asymptomatic during follow-up and 23 (34%) developed recurrent class III or IV angina at a mean of 2.6 +/- 1.2 months. Multivariate analysis of 22 clinical, angiographic and exercise test variables revealed that thallium-201 redistribution, any thallium scan abnormality, presence of a distal stenosis and treadmill time were the only significant predictors of recurrent angina after PTCA. Using a stepwise discriminant function model, thallium-201 redistribution was the only significant independent predictor. Despite its prognostic value relative to other variables as a predictor, thallium redistribution at 2 weeks after PTCA was only detected in 9 of the 23 patients (39%) who subsequently developed recurrent angina, although only 2 of the 45 patients (9%) who remained asymptomatic during follow-up demonstrated thallium-201 redistribution at the time of early testing. After repeat angiography was performed in 17 of the 23 patients with recurrent angina, 14 (82%) demonstrated restenosis and 3 (18%) had worse narrowing distal to or remote from the site of dilatation.(ABSTRACT TRUNCATED AT 250 WORDS)

Functional significance of predischarge exercise thallium-201 findings following intravenous streptokinase therapy during acute myocardial infarction

The purpose of this study was to determine which predischarge exercise thallium-201 imaging pattern(s) best correlate with myocardial salvage following intravenous streptokinase therapy (IVSK). Myocardial salvage was defined as improvement in regional left ventricular function determined by two-dimensional echocardiography between the time of admission and time of discharge in 21 prospectively studied patients receiving IVSK within 4 hours of chest pain. All patients had coronary angiography 2 hours following IVSK. Whereas 16 of the 21 patients (76%) had patent infarct-related vessels, only seven (33%) showed significant improvement in regional function at hospital discharge. Eleven patients demonstrated persistent defects (PD), and five each showed delayed and reverse redistribution. Patients with both delayed and reverse redistribution demonstrated significant improvement in regional left ventricular function score, while those with PD did not (+3.9 +/- 3.3 versus -0.5 +/- 2.9, p = 0.004). All other clinical, exercise, electrocardiographic, scintigraphic, and angiographic variables were similar between all patients, with the exception of the interval between chest pain and the institution of IVSK, which was longer in patients with reverse compared to delayed redistribution (3.5 +/- 0.4 versus 2.2 +/- 0.4 hours, p = 0.001). It is concluded that both delayed and reverse redistribution seen on predischarge exercise thallium-201 imaging are associated with myocardial salvage, defined as serial improvement in regional systolic function. Despite a high infarct vessel patency rate in patients with acute myocardial infarction receiving IVSK within 4 hours of onset of symptoms, only one third demonstrated improvement in regional function that was associated with either delayed or reverse redistribution seen on predischarge exercise thallium-201 imaging.

The clinical efficacy and scintigraphic evaluation of post-coronary bypass patients undergoing percutaneous transluminal coronary angioplasty for recurrent angina pectoris

The efficacy of percutaneous transluminal angioplasty in improving recurrent anginal symptoms and myocardial perfusion after coronary artery bypass graft surgery was assessed prospectively in 55 patients, of whom 50 had an initial angiographic and clinical success. Although 80% of those successfully dilated were initially free of angina at 23 +/- 11 months of follow-up, one half of these patients had recurrent angina. Although only 48% of the patient cohort had complete relief of angina, 94% had less angina than before dilatation and 86% were able to decrease antianginal medications. Fifteen patients with persistent or recurrent angina had from one to five repeat dilatations. After angioplasty, lung thallium uptake, the extent of abnormal scan segments, and the magnitude of redistribution in dilated lesions were significantly reduced (n = 24 patients). Redistribution defects were seen in 38% of patients on postangioplasty scans. All were associated with subsequent angina. Of various clinical, angiographic, exercise, and thallium-201 scan variables, only the presence of delayed redistribution was an independent predictor of recurrent angina. Restenosis was the most common underlying cause for this exercise-induced perfusion defect. Thus percutaneous coronary angioplasty performed as primary therapy for recurrent angina after bypass surgery is moderately successful in long-term follow-up for the amelioration of symptoms and enhancement of regional myocardial perfusion.

Acute coronary occlusion with exercise testing after initially successful coronary angioplasty for acute myocardial infarction.

Abstract Exercise testing is frequently performed within several days after percutaneous transluminal coronary angioplasty (PTCA) to assess the functional result of the procedure. 1,2 Early stress testing is considered safe, and few complications have been described. Dash 3 reported a case of acute coronary occlusion after early treadmill stress testing necessitating emergency bypass surgery. Herein we describe a patient in whom acute occlusion of the left anterior descending coronary artery (LAD) developed during symptom-limited exercise testing 5 days after angiographically successful PTCA.