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OBJECTIVES The purpose of this study was to compare quantitative ECG-gated single-photon emission computed tomography (SPECT) (QGS) and model-based ECG-gated single-photon emission computed tomography (MBGS) for determination of end-diastolic cardiac volume (EDV), end-systolic cardiac volume (ESV), and left ventricular ejection fraction (LVEF). The accuracy of both methods was evaluated by measurements obtained from contrast left ventriculography (LVG). METHODS Forty-five patients (40 male, age: 55+/-11 years) with coronary artery disease were studied by angiography and ECG-gated SPECT using technetium-99m-sestamibi for the evaluation of myocardial perfusion and LVEF. Short axis SPECT images were analyzed by QGS and MBGS to estimate endocardial and epicardial surfaces and to derive EDV, ESV, and LVEF. RESULTS EDV by gated SPECT (QGS: 187+/-71 ml; MBGS: 191+/-76 ml) were lower than corresponding values by LVG (203+/-59 ml), whereas ESV by gated SPECT (QGS: 121+/-62 ml; MBGS: 108+/-54 ml) were higher than by LVG (105+/-49 ml). Thus, LVEFs by gated SPECT (QGS: 39+/-12%; MBGS: 45+/-9%) were significantly lower than by LVG (50+/-15%). LVEF by MBGS was significantly higher than by QGS (P

The impaired compliance of large and medium-sized muscular arteries has been shown to correlate with the risk of adverse cardiovascular events. We assessed coronary artery distensibility using simultaneous intracoronary ultrasound and pressure wire measurements in porcine coronary arteries after implantation of paclitaxel-eluting (PES) and bare metal stents (BMS) and compared this with the histopathology of the arterial wall injury.PES and BMS were implanted into porcine left coronary arteries under general anesthesia. At 1-month follow-up (FUP) the endothelium-dependent and endothelium-independent vascular compliances were measured after intracoronary infusion of 10(-6)M acetylcholine for 2.5min, and intracoronary bolus of 100microg nitroglycerine, respectively. The arterial stiffness index, distensibility and reflexion index were calculated in stented arteries (n=25 PES and n=25 BMS), and correlated with histopathologic and histomorphometric changes of the vessel wall.In spite of smaller neointimal area, the fibrin deposition, medial thickening, vascular wall inflammation scores and arterial remodeling index were elevated and endothelialization was impaired in arteries with PES. Arteries with PES exhibited significantly worse endothelium-dependent vascular compliance: the stiffness (p0.001) and reflexion index (p0.001) were significantly higher and the distensibility index (p0.001) lower as compared with the arteries with BMS. The endothelium-independent vascular reaction was similarly impaired in arteries with PES, as the stiffness index (p0.001) and the distensibility index (p0.001) differed significantly between the PES and BMS groups. Incomplete endothelialization (r=0.617, p0.001) was significantly associated with the endothelium-dependent increased vascular stiffness. The increased fibrin score (r=0.646, p0.001), vessel wall inflammation (r=0.657, p0.001) and medial thickening (r=0.672, p0.001) correlated significantly with the endothelium-independent stiffness index.Implantation of PES impairs the coronary artery wall structure and the endothelium-dependent and independent vessel wall dynamics more than does the implantation of BMS.

Background: The aim of this present prospective study was to investigate the accuracy of cardiac markers for the prediction of subsequent cardiac events (cardiac death, acute myocardial infarction and recurrent ischemia requiring coronary revascularization). Methods: Fibrinogen, cardiac troponin T, troponin I, creatine phosphokinase myocardial fraction, C-reactive protein and myoglobin at baseline and after 6 h were measured on 154 patients (109 male, 63±11 years) with chest pain. Receiver operator characteristic analyses were performed to determine cut-off points of cardiac markers in prediction of adverse events. Results: The following cut-off values for prediction of cardiac events were calculated: troponin I at baseline 0.3 ng/ml (predictive accuracy=0.870), troponin I at 6 h 0.50 ng/ml (p.a.=0.909); troponin T at baseline 0.05 ng/ml (p.a.=0.643), troponin T at 6 h 0.05 ng/ml (p.a.=0.612), creatine phosphokinase myocardial fraction at baseline 2.0 ng/ml (p.a.=0.721), creatine phosphokinase myocardial fraction at 6 h 2.5 ng/ml (p.a.=0.734), myoglobin at baseline 23 ng/ml (p.a.=0.623), myoglobin at 6 h 26 ng/ml (p.a.=0.617), C-reactive protein at baseline 0.31 mg/dl (p.a.=0.662), C-reactive protein at 6 h 0.55 mg/dl (p.a.=0.682), and fibrinogen at baseline 360 mg/dl (p.a.=0.701). The combination of baseline troponin I with different parameters resulted in a higher sensitivity of up to 98%, with a similar predictive accuracy, but a lower specificity. Additive measurements of cardiac troponin I at 6 h to baseline cardiac troponin T and I proved to be the best combination for prediction of subsequnt cardiac events. Conclusions: Changes in cut-off levels of cardiac markers and inflammatory parameters results in a high accuracy of risk stratification in patients with chest pains. Combination of these measurements might further help in the identification of patients who would benefit from early coronary revascularization.

Die perkutane transmyokardiale Laser-Revaskularization (PTMR) wurde als Therapie fur Patienten mit konventionell nicht behandelbarer Angina pectoris angewendet, bei denen weder eine perkutane Koronarangioplastie noch eine Bypass-Operation moglich ist („no-option”-Patienten). Diese Studie untersucht die Kurz- und Langzeitergebnisse der zwischen Februar 1999 und Mai 2000 an der Universitatsklinik Wien durchgefuhrten PTMR-Behandlungen. Insgesamt 24 „no-option”-Patienten wurden einer PTMR unterzogen. Mittels Perfusionsszintigraphie wurde das chronisch ischamische Areal des linken Ventrikels bestimmt und nach Koronarangiographie und Kontrastventrikulographie 10 Patienten mit Biosense Laser unter NOGA-Mapping-3D-Navigation und 14 Patienten mit dem Eclipse-Laser unter konventioneller Rontgenkontrolle behandelt. Nach einer durchschnittlichen Follow-up (FUP)-Periode von 7,7±4,2 Monaten wurden bei allen Patienten Perfusionsszintigraphie, Koronarangiographie und Kontrastventrikulographie wiederholt. Die ischamischen Myokardbereiche der Patienten wurden mit durchschnittlich 16 Laserpunkten behandelt. Postinterventionell zeigte sich bei einem Patienten ein intramurales Hamatom (Biosense Laser), bei einem Patienten wurde mit dem Eclipse-Laser die Ventrikelwand perforiert (jeweils konservative Behandlung). Wahrend des Krankenhausaufenthalts litten 2 Patienten an schwerer Angina pectoris, ein Patient benotigte einen Schrittmacher. Im Laufe der FUP-Periode erlitt ein Patient einen Myokardinfarkt; ein Patient wurde mittels Stent-Implantation, ein weiterer mittels Bypass-Operation revaskularisiert (jeweils nicht-gelaserte Gebiete als Ziel), zwei Patienten starben (Gesamt-MACE-Rate 33,3%). Die pektanginose Symptomatik verbesserte sich wahrend des FUP signifikant, die Myokardperfusion blieb unverandert, die globale linksventrikulare Funktion zeigte jedoch einen Trend zur Verschlechterung. Wahrend sich die pektanginose Symptomatik wahrend der Nachuntersuchungsperiode signifikant verbesserte, zeigte sich keine signifikante Anderung der Myokardperfusion bei einem Trend zur Verschlechterung der Ventrikelfunktion.

Background and Objectives Myocardial perfusion and left ventricular function (LVF) were assessed after percutaneous transmyocardial laser revascularization (PTMR) in patients not amenable to conventional revascularization, with a comparison of two laser systems. Study Design/Materials and Methods PTMR was performed with an Eclipse laser in 15 patients, and with a Biosense DMR in 10 patients. 201Thallium scintigraphy, coronary angiography, and ventriculography were performed at baseline and at the 7.5±4.3-month follow-up. All patients in the Biosense DMR group and 10 in the Eclipse group underwent NOGA mapping before PTMR and after follow-up. Results The event-free survival rates were comparable, and the angina scores of all patients improved significantly, but more so in the Biosense DMR group than in the Eclipse group (1.2±1.1 vs. 2.3±0.9, P

Angiography of patients with typical chest pain reveals normal epicardial coronary arteries in about 20%. Coronary flow reserve (CFR) determination is an elaborate, but helpful, task, as only the evidence of microvascular disease enables appropriate therapy. We prospectively evaluated the incidence of a dysfunctional microcirculation and searched for predictive parameters of a reduced CFR.In 79 consecutive patients (52 females, 27 males) with typical angina and a normal angiogram and 10 control subjects (6 females, 4 males), CFR was measured by 13N-ammonia rest/dipyridamole PET and correlated with clinical parameters individually and summarized as the number of risk factors (NRF) using an elaborated cardiac risk factor score.Sixty-five percent of patients had a reduced CFR (CFR2.5). CFR correlated with NRF (r = 0.55, P0.001), systolic blood pressure (r = 0.46, P0.001), interventricular septal thickness (r = 0.33, P0.01), and age (r = 0.25, P = 0.02). Eighty-five percent of patients with a high risk factor score (NRFor = 5) had a reduced CFR. In contrast, 100% of our patients with a low risk factor score (NRF2) presented a normal CFR. In total, 55% of our patients could be allocated to either one of these groups.In about two thirds of patients, anginal pain can be explained by a reduced CFR. Risk factors have a cumulative negative effect on CFR. A clinical cardiac risk factor analysis enables estimation of individual probability of microvascular dysfunction in a significant proportion of these patients. However, CFR measurements are recommended for those with an intermediate NRF.