[Study of efficacy and safety of pharmacological stress tests in nuclear cardiology].

BACKGROUND/AIM: Treadmill test combined with myocardial perfusion scintigraphy (MPS) is a commonly used technique in the assessment of coronary artery disease. Many patients who cannot adequately perform exercise stress testing may nevertheless undergo pharmacological tests, most commonly with the vasodilator agents (adenosine and dipyridamole), as well as the positive inotropic agent dobutamine. Patients undergoing vasodilators stress testing with either dipyridamole or adenosine also perform simultaneous low-intensity exercise. The aim of this study was to compare various pharmacological stress tests alone or in combination with low intensity exercise as preparation for MPS in regard to incidence of adverse effects, quality of diagnostic image and the acquisition initial time. METHODS: A total of 2 205 patients underwent pharmacological stress tests. Pharmacological stress test with adenosine was applied in 493 patients. In 405 of them we performed concomitant low level exercise (50 W) by bicycle ergometar (AdenoEX). In 88 of them we performed adenosine abbreviated protocol (AdenoSCAN). In 1 526 patients we performed pharmacological stress test with dipyridamole. In 871 of them we performed concomitant low level exercise (50 W) by bicycle ergometar (DipyEX), and in 775 we used only dipyridamole protocol (DipySCAN). In 186 patients we used pharmacological stress test with dobutamine. We followed side effects of adenosine, dipyiridamole and dobutamine, compared results between protocols with concomitant low level exercise and vasodilatators only. We also compared image quality, and suggested time of acquisition after stress test. RESULTS: We found numerous side effects especially with adenosine, but these effects were short-lived and not required active interventions. Benefit with concomitant exercise in booth AdenoEX and DipyEX included decreased side effects (AdenoEX vs AdenoSCAN 620% vs 87%, respectively, and DipyEX vs DipySCAN 37% vs 59%, respectively) improved safety and patients tolerance, improved target-to-background ratios because of less subdiaphragmal activity, and earlier acquisition time. Because of producing a lot of arrhythmias (in 49% of patients) dobutamin was considered a last choice for pharmacological stress testing. CONCLUSION: Safety and efficacy of vasodilatators (adenosine, dipyridamole) pharmacological stress tests are good, but with concomitant exercise even better. The safety and efficacy of adenosin are better than those of dipyridamole. AdenoEX protocol provides good safety and patients tolerancy. In light of these benefits we recommend AdenoEX whenever possible. Dobutamine is the last pharmacological toll for MPS.

[Diagnostic significance of myocardial perfusion scintigraphy in identification and localisation of culprit lesions in patients undergoing elective PTCA].

BACKGROUND/AIM: The coronary angiography provides information on the anatomical state of the coronary tree, while myocardial perfusion scintigraphy (MPI) facilitates the evaluation of the grade of ischaemia that a particular stenosis produces. The purpose of MPI is to detect the coronary stenosis that provokes the ischaemia and is termed the "culprit lesion". The aim of this study was to evaluate the accuracy of 1-day DypEX 99mTc-tetrofosmin tomography in the identification and localization of culprit lesion in the patients with known coronary artery disease (CAD). METHODS: Ninety-one (91) patients with known CAD were studied. In all of them significant coronary narowing (> 75% luminal stenosis) was angiographically detected. All the patients were submitted to 2 i.v. injections of 99mTc-tetrofosmin, one in a peak of pharmacologic dipyridamole stress protocol with concomitant low level bicycle exercise 50W (DypEX) and the other 3 h after exercise. Quantification of regional tetrofosmin uptake was performed using short-axis myocardial tomogram that was divided on 17 segments for each study. Reversibility score (RS) > or =3 determinated culprit lesion. Two of segments with scor 5 (index of reversibility scor--IRS) in the territory of coronary artery stenoses determinated culprit lesion. RESULTS: A total of 273 vascular territories (4641 segments) were analyzed before percutaneous coronary intervention (PCI). Overall sensivity, specificit, and accuracy using RS > or =3 and IRS were 90.1%, 87.1%, 89.4%, with positive predictive value 95.8%, and 94.1%, 93.3%, 94%, with positive predictive value 98%, respectively. CONCLUSION: RS and IRS significantly improve sensitivity, specificity, and accuracy for determination of culprit lesion in patients undergoing PCI.

[Adenosine stress protocols for myocardial perfusion imaging].

BACKGROUND/AIM: Treadmill test combined with myocardial perfusion scintigraphy (MPS) is a commonly used technique in the assessment of coronary artery disease. There are many patients, however, who may not be able to undergo treadmill test. Such patients would benefit from pharmacological stress procedures combined with MPS. The most commonly used pharmacological agents for cardiac stress are coronary vasodilatators (adenosine, dipyridamol) and catecholamines. Concomitant low-level treadmill exercise with adenosine pharma cologic stress (AdenoEX) during MPS has become commonly used in recent years. A number of studies have demonstrated a beneficial impact of AdenoEX protocol. The aim of the study was, besides introducing into practice the two types of protocols of pharmatological stress test with adenosine, as a preparation for MPS, to compare and monitor the frequency of their side effects to quality, acquisition, as well as to standardize the onset time of acquisition (diagnostic imaging) for both protocols. METHODS: A total of 130 patients underwent pharmacological stress test with adenosine (vasodilatator). In 108 of the patients we performed concomitant exercise (AdenoEX) of low level (50W) by a bicycle ergometar. In 28 of the patients we performed Adenosine ab breviated protocol (AdenoSCAN). Side effects of adenosine were followed and compared between the two kinds of protocols AdenoEX and AdenoSCAN. Also compared were image quality and suggested time of acquisition after the stress test. RESULTS: Numerous side effects were found, but being short lived they did not require any active interventions. The benefit of AdenoEX versus AdenoSCAN included decreased side effects (62% vs 87%), improved safety and patients tolerance, improved target-to-background ratios because of less subdiaphragmatic activity, earlier acquisition, and improved sensitivity. CONCLUSION: The safety and efficacy of adenosine pharmacological stress is even better with concomitant exercise. In the light of these benefits we recommend AdenoEX whenever possible.

[Myocardial damage size assessment in the zone of infarction for indicating rescue percutaneous coronary intervention].

BACKGROUND: The most important predictors of subsequent patients outcome after acute myocardial infarction (AIM) are infarct size, left ventricular ejection fraction, left ventricular volumes and presence and extent of residual myocardial ischemia. All of these variables can be directly determined through scintigraphic approaches. The presence and extent of myocardial ischemia are strong pre dictors for fatal and nonfatal cardiac events and improve risk statification beyound the information gleaned from clinical variables. CASE REPORT: We presented a case of 66-years-old male with myocardial infarction of anteroseptal localization. Myocardial perfusion imaging (MPI) detected a large zone of residual ischemia (culprit lesion) within infarction zone. It has an important role in risk stratification after myocardial infarction, and indicates subsequent therapeutic decision making, in this case rescue percutaneous coronary intervention (PCI). After PCI we followed the therapy effect by MPI, and we found practically normal perfusion with minimal zone of defect perfusion in the apex. CONCLUSION: Myocardial perfusion imaging has an important role in the initial evaluation and risk stratification of patients surviving myocardial infarction. It also plays a major role in guiding subsequent therapeutic decision making, and in monitoring the benefits of these therapeutic measures.

[Percutaneous transluminal coronary angioplasty in the right ventricle myocardial infarction treatment].

BACKGROUND/AIM: To present the results of percutaneous transluminal coronary angioplasty (PTCA) in the treatment of the patients with acute right ventricle myocardial infarction (ARVMI), with adjuvant analyses of the obtained results in the period of five years (2000-2004). METHODS: Thrombolytic therapy and the primary percutaneous transluminal coronary angioplasty (PPTCA) was applied within the first 6 hours from the onset of anginous disorders, and rescue PTCA in the period from 6-24 hours from the onset of ARVMI. Results. A total number of 1175 patients, both sexes, 763 (64.8%) males and 412 females (35.2%), mean age 58.4 +/- 7.8 years, were treated for acute myocardial infarction (AIM) of different localization in the period of five years (2000-2004). Anterior infarction was found in 645 (54.8%) of the patients, and inferoposterior infarction (IPI) was localized in 530 patients (45.2%) patients of which in 134 (25.2%) AIMDK was proven. Out of 134 patients with proven acute myocardial of the right ventricle AIMDK, 53 (39.5%) got thrombolytic therapy, 64 patients (47.7%) were treated with the conservative heparin therapy, whereas in 17 patients (12.8%), primary percutaneous coronary angioplasty (PPTCA) was done. Delayed or rescue PTCA was done in 22 (18.8%) patients, in 8 (36.3%) from the group which got thrombolytic therapy, and in 14 (63.7%) treated with the heparin therapy. Out of the total number of 22 patients who got heparin or thrombolytic therapy combined with rescue PTCA, in 7 patients (31.8%) the complete clinical and angiographic effect of thrombolysis with AIM was achieved only by using a balloon. Baloon dilatation with the implantantion of intracoronary stent was performed in another 11 patients (50%), while 2 (9.1%) were sent to revascularization of the myocard due to diffusion changes in each of the 3 blood vessels, and 2 patients (9.1%) died. Of the patients, 17 (12.6%) had PPTCA with the implantation of intracoronary stent with the additional direct inhibitor of the platelet membrane glycoproteins IIb/IIIa (abciximab). All the patients treated in this way survived. They had no side effects nor serious complications. Their clinical recovery was satisfactory. In the first three weeks of the intrahospital period in the group of 45 patients (33.5%) with AIMDK, who got only thrombolytic therapy, 7 patients (15.5%) died, whereas in the group of 50 patients (37.3%) treated only with heparin, 13 (26%) died. In the group of 22 patients (18.8%) treated with the combined therapy with rescue PTCA and heparin or thrombolytic therapy, 2 patients (9.1%) died. In the group of 84 patients (62.6%) with AIMDK, who were treated with thrombolytic therapy with primary or rescue PTCA, 9 (10.7%) died. In the AIMDK group of 134 patients, 22 patients (16.4%) died in the period of 1 month of the hospital treatment, whereas in the second group of 396 patients with IPI, but without IDK, 36 (9.1%) died (chi2 = 4.789; p < 0.001). Out of the total number of 1175 patients with AIM in the five-year period of the intrahospital treatment, 145 patients (12.3%) died. In the group of patients with IPI, 58 patients out of 530 (10.9%) died, whereas 87 patients out of 645 (13.4%) with anterior infarction died, (chi2 = 0.567; p < 0.452). CONCLUSION: The combination of thrombolytic therapy and PTCA shown in the obtained results completely justified this kind of treatment, and offered the patients with AIMDK a greater chance to surve than they had before.

[The results of the treatment of right ventricle myocardial infarction].

AIM: To present the results and experience in diagnosing and treating of patients with acute right ventricle infarction, during the period of hospitalization of one month, with adjuvant analyses of the obtained results in the period of fifteen years. METHODS: Acute right ventricle infarction porved clinicaly, enzymologicaly, by ECG, echochardiographically or scintigraphically we treated with thrombolitic therapy within first six hours after admittion, with salvaged PTA in case of the cardiogenic shock or AV block II degrees-III degrees despite of thrommbolitic therapy, or with postponed PTA within first month of intrahospital treatment. RESULTS: In the period from 1990 to 2004, 3 225 patients of both sexes were treated for acute myocardial infarction at the different localization in patients' at the mean age of 53.7 +/- 5.8. One-hundred-thirty-nine (43.9%) patients were treated with thrombolitic therapy according to the speed up protocole. Heparin was administered to 160 (50.7%) patients with water load, and 17 (5.4%) patients had the primary percutaneous transluminal coronary angioplasty (PPTCA), so that the mechanical blood flow could be established, by the implantation of a stent when necessary. In 316 patients with right ventricle infarction, 58 (18.3%) had postponed and salvaged percutaneous transluminal coronary angioplasty (PTCA). Twenty-two (15.8%) patients had thrombolitic therapy, whereas 36 (22.5%) patients were treated with heparin. We had a successful balloon dilatation in 21 (36.2%), whereas 32 (55.2%) patients had 1-3 intracoronary stents inplanted, depending upon the necessity, and 5 (8.6%) patients from this group were sent to surgical intervention. In the group of 214 (67.7%) patients treated with heparin or thrombolitic therapy combined therapy, with PTCA, 12 (5.7%) patients died, whereas in the group of 124 (39.3%) patients treated only with heparin 26 (16.2%) patients died, statistically significant difference (p < 0.001, chi2 = 18.423). Was noticed n the group of 1 204 patients with inferoposterior infarction, 122 (10.1%) patients died. In the group of 316 patients with right ventricle infarction, 38 (12%) died. In the group of 888 control patients with inferoposterior infarction, but without right ventricle infarction, 84 (9.4%) patients died. In the group of 2 021 patients (62.2%) with anterior infarction, 248 (12.3%) died. CONCLUSION. The obtained results showed that the patients with right ventricle infarction, due to the great expansion of necrosis and the involvement of the inferoposterior wall of the left ventricle, as well as the ischemia of sinus and AV nodes, were the patients of a high risk. That was why it was essential to do urgent widening of the artery to reestablish blood flow either by using drugs or by means of mechanical methods.

Primary percutaneous transluminal coronary angioplasty in the acute infarction of the right ventricle.

BACKGROUND: Predilection site for the acute myocardial infarction of the right ventricle, (AMI-RV) is the upper third of the right coronary artery and for this reason such an infarction is followed by numerous complications, primarily by conduction disorders and very often by sudden and rapid cardiogenic shock development. METHODS: Primary percutaneous transluminal coronary angioplasty (PPTCA) was performed on three patients, in whom the acute infarction of the right ventricular was diagnosed and who had been hospitalized six hours after the beginning of chest pain. In all three patients intracoronary stent was implanted. On the admission patients had been in the threatening cardiogenic shock, with the prominent chest pain and with the elevation of ST-segment in V4R > 2 mV. In the course of intervention patients were administered low-molecular intracoronary heparin, with direct platelet glycoprotein IIb/IIIa inhibitors (abciximab), according to the established procedure applied in such cases. RESULTS: The complete dilatation of the infarcted artery was established with the signs of reperfusion and the further clinical course was completely normal, there was no heart failure and patients had no subjective difficulties. CONCLUSION: Invasive approach in the treatment of AMI-RV is justifiable, and possibly the therapy of choice of these patients, providing well trained and equipped team is available.

Current therapy of the right ventricle myocardial infarction.

BACKGROUND: Acute myocardial infarction of the right ventricle (AMI-RV) is a separate subgroup within the scope of inferoposterior infarction of the left ventricle. It still represents the population of patients at high risk due to numerous, often hardly predictable complications and high mortality rate. METHODS: In fifteen-year period (1987-2001) 3,765 patients with the acute myocardial infarction (AMI) of different localizations of both sexes--2,283 males and 1,482 females of the average age 61.4 +/- 4.6 years were treated in our institution. Anterior myocardial infarction was diagnosed in 2,146 (56.9%) patients, inferior in 1,619 (43.1%) patients, out of whom right ventricular infarction (RVI) was confirmed in 384 (23.7%). Thrombolytic therapy was administered in 163 (42.4%) patients with RVI, and in 53 (41.7%) of these patients balloon dilatation was performed with coronary stent implantation in 24 (45.2%). RESULTS: Favorable clinical effect of the combined thrombolytic therapy and percutaneous transluminal coronary angioplasty (PTCA) was achieved in 51 (96.1%), and in only 2 (3.9%) of patients the expected effect wasn't achieved. Myocardial revascularization was accomplished in 6 (3.6%) and 1 patient died. In 3 (3.4%) patients primary balloon dilatation with the implantation of intracoronary stent was performed within 6 hours from the onset of anginal pain. In the other group of 221 (57.5%) patients with RVI who did not receive thrombolytic therapy, or it had no effect, 26 (11.7%) patients died, which indicated the validity and the efficacy of this treatment (p < 0.01). In the whole group of patients with myocardial infarction of the right ventricle 31 (8.1%) died; in the group that received thrombolytic therapy and PTCA 5 (3.1%) died, while in the group treated in a conservative way 26 (11.7%) died. CONCLUSION: Combined therapy was successful in the treatment of patients with RVI and should be administered whenever possible, since it was the best prevention of life-threatening complications and the decrease in the mortality of those patients.

[Treatment of acute myocardial infarct with ST segment elevation with a combination of fibrinolytic therapy and abciximab]. / Primena kombinacije fibrinoliticke terapije i abciksimaba u lecenju akutnog infarkta srca sa elevacijom ST segmenta.

BACKGROUND: According to current knowledge, the best way to treat the acute myocardial infarction with ST elevation is primary transluminal coronary angioplasty, which can be performed only in the best equipped tertiary cardiology centers. As it was known that atherothrombosis wais the essence of the acute coronary syndrome we wanted to examine the efficacy and safety of combined therapy of tissue plasminogen activator and glycoprotein IIbIIIa platelet receptor antagonist abciximab. METHODS: The case is reported of combined abciximab and accelerate schedule of t-PA reperfusion therapy in a young patient with the extensive anterior acute myocardial infarction. Activated partial thromboplastin time and platelet count were regularly measured during therapy. RESULTS: The combination of these two drugs did not cause any complication in our patient. According to early noninvasive parameters, successful reperfusion was achieved. Postinfarction period was without complications. Coronary angiography was performed 15 days after and was without pathological findings. Eighteen months later the event patient had neither chest pain, nor other complaints with slightly reduced R waves in middle precordial leads and hypokinesis of anterior apical segment of the left ventricle showing the signs of important systolic function impairment. CONCLUSION: Controlled studies are needed to prove the safety and the benefit of such combined reperfusion therapy and to show which kind of treatment is appropriate in every case considering the patient conditions and the facilities of coronary care unit.