Adjunctive thrombus aspiration and mechanical protection from distal embolization in primary percutaneous intervention for acute myocardial infarction.

Primary percutaneous intervention for acute occlusion of a native coronary artery may be complicated by distal embolization of plaque or thrombotic debris, with infarct extension. We tested the clinical application of a new therapeutic strategy combining maximal antiplatelet therapy, with glycoprotein IIb/IIIa inhibition, and adjunctive mechanical protection from distal embolization and direct aspiration of thrombus with a new balloon and catheter system (PercuSurgetrade mark). Successful aspiration of thrombus could be obtained in 7 out of 8 attempted procedures, with inability to negotiate the angulated take-off of the circumflex coronary artery in one patient. The current mechanical characteristics of the device, primarily developed for use in larger saphenous vein grafts, and certain caveats and limitations are discussed. New dedicated systems should be available in the near future for the native coronary circulation. Excellent immediate angiographic results were obtained in all treated patients, without evidence of loss of distal branches and no intraprocedural complications.

Dipyridamole thallium-201 imaging very early after uncomplicated acute myocardial infarction in patients treated with thrombolytic therapy.

The aim of this study was to assess the safety and prognostic value of dipyridamole 201T1 imaging very early after acute myocardial infarction in patients treated with thrombolytic therapy. Fifty-two consecutive patients with an uncomplicated clinical course underwent quantitative planar dipyridamole 201T1 imaging 2 5 days after acute myocardial infarction. The patients were followed for 14 +/- 7 months after discharge. No major complications occurred during the test. Of the 30 patients with redistribution, five (16.6%) developed in-hospital unstable angina as against none of the 22 patients without redistribution. During follow-up, a total of live late cardiac events were observed: two deaths and two cases of unstable angina in the group with reversible defects and one reinfarction in the group with fixed defects. The 1-year actuarial probability of being free of cardiac events was, respectively, 66 +/- 10% and 94 +/- 5% in the patients with and without redistribution (P < 0.01). In conclusion, in patients treated with thrombolysis, dipyridamole-201T1 imaging very early after uncomplicated acute myocardial infarction is a feasible and safe test. Patients with fixed defects appear to be at low risk and may be candidates for early discharge; the presence of redistribution identifies a subgroup of patients who may benefit from further careful clinical evaluation.

Strategy of diagnostic imaging before and after PTCA.

It is now widely accepted that percutaneous transluminal coronary angioplasty (PTCA) is an effective nonsurgical technique for achieving coronary revascularization. Exercise electrocardiography remains the standard procedure for functional evaluation before, early, and late after angioplasty because of its availability, safety, and limited cost. The drawback of exercise testing is its low specificity and the fact that the attainment of diagnostically useful data requires a level of exercise that substantially increases myocardial oxygen demand. Exercise thallium imaging has been shown to be highly predictive of restenosis and adverse events after angioplasty, but it is possible that myocardial perfusion may not return to normal immediately after successful revascularization. Stress echocardiography has many practical advantages over scanning tests, as result of its lower cost, shorter imaging time, and the absence of radiation exposure. Dipyridamole echocardiography testing (DET) is an exercise-independent method of evaluating patients who have to undergo coronary angioplasty. Before PTCA, DET allows the clinician to localize the site and extent of myocardial ischemia anatomically. Early after a successful procedure, DET identifies a group at high risk for the late recurrence of symptoms. Late after PTCA, DET is more accurate than exercise electrocardiography in detecting restenosis or disease progression. In asymptomatic patients with exercise-induced ST depression, DET has the same good diagnostic accuracy as thallium scintigraphy. For these reasons, as well as because of its noninvasive nature and availability, DET should be considered an attractive option for the evaluation of patients after anatomically successful angioplasty.

Exercise thallium scintigraphy versus high-dose dipyridamole echocardiography testing for detection of asymptomatic restenosis in patients with positive exercise tests after coronary angioplasty.

The usefulness of high-dose (< or = 0.84 mg/kg over 10 minutes) dipyridamole echocardiography testing was compared with that of exercise thallium-201 scintigraphy in detecting restenosis (> 70% lumen reduction) in 50 asymptomatic patients with ST-segment depression during maximal exercise testing 3 months after successful coronary angioplasty. Dipyridamole echocardiography testing and exercise thallium scintigraphy showed a similar sensitivity (75 vs 83%; p = NS) and specificity (90 vs 84%; p = NS) for the detection of restenoses, which occurred in 12 patients. It is concluded that dipyridamole echocardiography testing is as accurate as exercise thallium testing for the noninvasive detection of severe restenosis in patients with exercise-induced asymptomatic ST-segment depression after successful angioplasty. Furthermore, the site, extent and severity of the thallium perfusion defects during exercise are correlated to those of the dyssynergy during dipyridamole echocardiography.

Coronary artery disease after heart transplantation: non-invasive evaluation with exercise thallium scintigraphy.

In order to assess the value of exercise thallium scintigraphy for the detection and prognosis of graft coronary artery disease, 50 heart transplant patients (mean age 46.7 +/- 11.5 years) were studied within 48 h of their scheduled yearly coronary angiography and subsequently followed up for a mean of 13 +/- 3 months. Angiography revealed normal coronary arteries in 35 patients, and coronary artery disease in 15 (two with type A lesions, seven with type B lesions and six with both). Seven patients had one or more stenoses > or = 50%. Exercise thallium scintigraphy was negative in all patients with normal coronary arteries (100% specificity), and abnormal in 10 of 15 patients with coronary artery disease (67% sensitivity). Fixed defects were seen in six cases, transient defects in two and both in two; the results of the test were abnormal in all seven patients with > or = 50% lesions. During follow-up, none of the patients with a normal exercise thallium scintigraphy experienced any cardiac event; in the group with abnormal results, four cardiac events occurred. Although further studies are needed to confirm these results, exercise thallium scintigraphy seems to be useful in evaluating post-transplant coronary artery disease: it is accurate in detecting the most severe stenoses and provides some prognostic information.

Value of negative predischarge exercise testing in identifying patients at low risk after acute myocardial infarction treated by systemic thrombolysis.

Although thrombolytic therapy reduces mortality in patients with acute myocardial infarction (AMI), it is associated with a greater incidence of successive coronary events, and there is still no ideal diagnostic and therapeutic strategy for such patients. The present study verifies the value of negative predischarge exercise testing in identifying low-risk patients treated with thrombolysis after AMI. One hundred fifty-seven consecutive patients with an uncomplicated clinical course underwent maximal or symptom-limited exercise testing (Bruce treadmill protocol) within 15 days of AMI in the absence of therapy. The location of the AMI was anterior in 51 patients, inferior in 85 and non-Q-wave in 21. All of the patients were followed for 6 months. Death and nonfatal reinfarction were considered as major coronary events, and the recurrence of angina as a minor event. Exercise test results were negative in 105 patients (group 1) and positive for angina or ST depression greater than or equal to 0.1 mV in 52 (group 2). No deaths occurred during follow-up; there were 3 reinfarctions (3%) and 7 cases (7%) of postinfarction angina in group 1, and 2 reinfarctions (4%) and 21 cases (40%) of postinfarction angina in group 2. By the end of follow-up, 90% of the patients with negative exercise test results were event-free (97% in the case of major events). These results show that thrombolytic therapy does not affect the value of negative postinfarction exercise testing in identifying low-risk patients.

Comparison of usefulness of high-dose dipyridamole echocardiography and exercise electrocardiography for detection of asymptomatic restenosis after coronary angioplasty.

The present study compares the relative usefulness of the maximal treadmill exercise electrocardiography test with the high-dose dipyridamole echocardiography test (echocardiographic monitoring during dipyridamole infusion up to 0.84 mg/kg in 10 minutes) in detecting severe restenosis or coronary artery disease progression (greater than 70% stenosis) in asymptomatic patients 12 months after a primary successful coronary angioplasty. Criteria of positivity were: for the exercise electrocardiography test, an ST-segment shift greater than or equal to 0.1 mV from baseline, 0.08 second from the J point; for the dipyridamole echocardiography test, a transient dyssynergy of contraction, absent or of a lesser degree than that in the baseline examination. The exercise electrocardiography and dipyridamole echocardiography tests revealed a similar feasibility (91 vs 87%, difference not significant). Both tests could be performed in 75 patients. For detection of restenosis or disease progression, or both, the exercise electrocardiography test revealed a sensitivity similar to the dipyridamole echocardiography test (71 vs 71%, difference not significant), but a lower specificity (61 vs 90%). It is concluded that the high-dose dipyridamole echocardiography test is equally feasible but more accurate than the exercise electrocardiography test for noninvasive detection of severe asymptomatic restenosis or disease progression at 1 year after successful coronary angioplasty.

Exercise electrocardiography versus dipyridamole echocardiography testing in coronary angioplasty. Early functional evaluation and prediction of angina recurrence.

Recently, we have shown the usefulness of high-dose dipyridamole echocardiography testing (DET) as an exercise-independent method for the evaluation of patients having coronary angioplasty. The purpose of the present study was to determine the value of DET compared with exercise testing in the early functional evaluation after successful percutaneous transluminal coronary angioplasty (PTCA) and in the prediction of late recurrence of angina. We performed DET and exercise testing in 52 consecutive patients both before and after successful PTCA. Criteria of positivity for DET were transient dyssynergy absent or negligible in the baseline examination and exercise testing for an ST segment shift greater than 0.1 mV from baseline. All patients had an angiographically successful PTCA: the percent stenosis went from 78 +/- 7% before to 30 +/- 7% after PTCA. Exercise testing was positive in 49 and 29 patients, respectively, before and after PTCA (94% versus 44%, p less than 0.001). DET was positive in 47 patients before and in 10 after PTCA (90% versus 19%, p less than 0.001). Recurrence of angina was found in 18 patients: 14 of 23 with positive and four of 29 with negative exercise testing after PTCA. With DET, recurrence of angina was found in eight of 10 patients with positive and 10 of 42 with negative DET after PTCA.(ABSTRACT TRUNCATED AT 250 WORDS)

Exercise testing and dipyridamole echocardiography test before and 48 h after successful coronary angioplasty: prognostic implications.

The purpose of the present study was to determine the value of exercise testing (ET) and dipyridamole echocardiography test (DET) in the early functional evaluation after a successful coronary angioplasty (PTCA) and in the prediction of angina recurrence. 52 patients underwent ET and DET before and 48 h after a successful PTCA. During a 6-12 month follow-up period they all underwent clinical evaluation. Before PTCA, ET was positive in 49 of 52 patients (94%) and new asynergies were detected by DET in 47 of 52 patients (90%). 48 h after PTCA 23 patients (44%) had positive ET results and 10 had a positive DET response. During the follow-up, 17 patients experienced recurrence of angina. Positive predictive value (PPV) for angina recurrence of ET and DET performed early after the PTCA were, respectively, 57 and 80%. The PPV of ET increased to 88% when electrocardiographic (ECG) positivity was accompanied by angina. Negative predictive values of ET and DET were, respectively, 86% and 79%. Early after PTCA, exercise ECG positivity was not predictive of symptom recurrence while ECG positivity associated with angina revealed a high PPV, similar to that of DET.

[Role of ambulatory ECG in the diagnostic work of a cardiology division]. / Ruolo dell'ECG dinamico nell'iter diagnostico in una Divisione di Cardiologia.

Holter monitoring may be effected during hospitalization either for clinical research or for high-risk patients or after surgical treatments. In the other cases, if possible, it should be better to effect ambulatory electrocardiographic monitoring in patients engaged in their normal daily activity nevertheless reducing hospital costs. Last year, in our department we effected 2420 Holter monitoring, of which 44% for patients hospitalized in our department, 11% hospitalized in other divisions, 44% for ambulatory patients. Holter monitoring was effected in the 35% of patients to detect arrhythmias, in the 29% for the evaluation of the effect of antiarrhythmic therapy; the 28% of Holter monitoring was recorded for patients recovering from acute infarction. Holter monitoring, associated to the other cardiological screening tests, has a very important rule for diagnosis of arrhythmias or myocardial ischemia, prognostic evaluation of cardiopathic patients (ischemic heart disease, cardiomyopathies, valvular and congenital heart disease), verification of the effects of therapy (PTCA, surgical and antiarrhythmic treatment).

[Prognostic setting and bloodless hemodynamic evaluation of acute myocardial infarct with equilibrium radioisotopic ventriculography]. / Inquadramento prognostico e valutazione emodinamica incruenta nell'infarto miocardio acuto con ventricolografia radioisotopica all'equilibrio.

Forty-four consecutive patients with acute myocardial infarction were studied with equilibrium radionuclide angiography (RNA) within 24 hours from the onset of symptoms, three days after admission and three days before hospital discharge (14 +/- 3 days). To assess the prognostic value of RNA derived parameters we assessed: the ejection fraction (EF), the left ventricular end-systolic volume index (ESVI), the left ventricular end-diastolic volume index (EDVI), the cardiac index (CI), the stroke volume index (SVI) and the peak systolic pressure/end-systolic volume index ratio (PSP/ESVI); we also determined Peel's prognostic index (PI) on admission and measured systolic arterial pressure (SAP), diastolic arterial pressure (DAP) and cardiac frequency (CF) as the same time as the radioisotopic parameters were taken. Thirty-nine patients were discharged without signs of ventricular failure with and without medical treatment (group A), 5 died during hospitalization (group B). Using EF alone, we obtained a very clear distinction between the two groups (Group A 43 +/- 12%; Group B 22 +/- 3%; p less than 0.005). Stepwise, multivariate analysis showed that, by linking PSP/ESVI to EF, we can even obtain a function that correlate better with hospital survival (F = 0.09832 X EF - 0.32035 X PSP/ESVI - 3.12981; p less than 0.002). There was good exponential correlation between EF and PSP/ESVI (r = 0.781) and this would seem to confirm that PSP/ESVI is a more sensitive contractility index for patients with a not very depressed EF.

[Assessment of coronary stenosis by myocardial scintigraphy with thallium-201 after dipyridamol infusion]. / Evidenziazione di stenosi coronariche mediante scintigrafia miocardica con tallio-201 dopo infusione di dipiridamolo.

After a 4 minute i.v. dipyridamole infusion (0.14 mg/Kg/min) serial Thallium-201 scans were obtained in 45 patients, without myocardial necrosis, undergoing coronarography. Twelve patients had effort angina, 6 rest angina, 14 effort associated with rest angina, 13 had atypical chest pain. Thirty-two patients had a 50% or greater stenosis of 1 or more coronary artery (8 had three vessels disease, 7 two vessels, 17 one vessel); 13 patients had no significant coronary stenosis ("control group"). The test induced electrocardiographic signs of ischemia in 18 patients, all with significant coronary stenosis, 15 of them experienced angina too. Sensitivity of Thallium-201 for detecting coronary artery stenosis was 94% (30 of 32) and specificity was 85% (11 of 13). In the group of the 17 patients with one vessel disease we obtained a sensitivity and specificity of 100% (17 of 17). We conclude that Thallium-201 myocardial imaging after pharmacologic vasodilatation with dipyridamole is a highly sensitive and specific test for detecting coronary artery stenoses without necessary overt ischemia. In fact dipyridamole, as consequence of its important coronary vasodilatation, produces differences in myocardial perfusion with relative perfusion defects detectable with Thallium-201 imaging.