A. J. Morguet

Complication Rate of Right Ventricular Endomyocardial Biopsy via the Femoral Approach A Retrospective and Prospective Study Analyzing 3048 Diagnostic Procedures Over an 11-Year Period

Background— An unequivocal diagnosis of myocarditis and cardiac virus persistence is based on histological, immunohistological, and molecular biological analyses of endomyocardial biopsies (EMBs). Biopsy-based diagnosis of myocarditis has become increasingly important because recent studies have demonstrated the beneficial effects of biopsy-based causal treatment strategies (immunosuppressive or antiviral). Because the risks of major complications caused by EMB procedures have not yet been well defined, we evaluated the incidence of major and minor complications of right ventricular EMB procedures in this retrospective and prospective single-center study. Methods and Results— With the use of a modified Cordis bioptome, 1919 patients underwent 2505 EMB procedures retrospectively over a 9-year period (January 1995 to December 2003), and 496 patients underwent 543 EMB procedures prospectively between January 2004 and December 2005. A total of 2415 patients had 3048 EMB procedures via the right femoral vein approach under biplane fluoroscopic control to evaluate unexplained left ventricular dysfunction (retrospective left ventricular ejection fraction, 49.8±18.8%; prospective, 48.8±19.7%) after exclusion of secondary causes. During each EMB procedure, an average of 8.2±0.8 EMBs were obtained retrospectively and 10.1±0.6 specimens prospectively for a total of 26 025 specimens. No patient died or required emergency cardiac surgery. Other major complications like cardiac tamponade requiring pericardiocentesis or complete atrioventricular block requiring permanent pacing were very rare: 0.12% in the retrospective study and 0% in the prospective study. Minor complications such as pericardial effusion, conduction abnormalities, or arrhythmias occurred in 0.20% of the EMB procedures in the retrospective study and 5.5% in the prospective study. Conclusions— The EMB procedure via the femoral vein approach under fluoroscopic guidance has a very low complication rate when performed by experienced operators.

Prehospital versus periprocedural abciximab in ST-elevation myocardial infarction treated by percutaneous coronary intervention.

Objective To investigate the potential benefit of an earliest possible out-of-hospital start of abciximab (ReoPro) therapy in ST-elevation myocardial infarction (STEMI; Lilly, Bad Homburg, Germany) and planned primary percutaneous intervention compared with periprocedural abciximab treatment on reperfusion and clinical outcome. Methods Randomization of one hundred and one patients with STEMI to prehospital or periprocedural abciximab treatment. Evaluation of thrombolysis in myocardial infarction (TIMI) flow, ST-segment resolution, myocardial blush grade, and maximal creatine kinase release before and after as well as clinical follow-up until 6 months after the index event. Results Prehospital abciximab (group 1) was initiated a median of 101 min (37–165 min) earlier compared with periprocedural treatment (group 2). Initial TIMI 3 flow (24 vs. 15%, P=NS), ST-segment resolution before percutaneous coronary intervention (PCI) (<30%: 33 vs. 46%, P=NS; >70%: 38 vs. 33%, P=NS), post-PCI myocardial blush grade 2 and 3 (72 vs. 75%, P=NS), maximal cardiac enzyme release (creatinine kinase MB median 77 U/l; range 33–137 vs. 74 U/l; range 39–143 U/l, P=NS), and 6 months follow-up (recurrent myocardial infarction or repeat coronary intervention, and PCI, need for coronary bypass surgery) did not differ significantly between both treatment groups. Conclusion Prehospital intravenous administration of abciximab, although safe and feasible in a trained surrounding, does not add angiographic or clinical benefit to patients with STEMI.

The impact of vessel and catheter position on the measurement accuracy in catheter-based quantitative coronary angiography

Background: The calculation of absolute artery dimensions in quantitative coronary angiography is usually carried out by catheter calibration. It is based on the proportional comparison of the dimension of the imaged artery segment to the dimension of the imaged angiographic catheter of known size. This calibration method presumes an identical radiographic magnification between angiographic catheter and artery segment of interest. However, due to the different intrathoracic location of both objects the radiographic magnification or calibration factor is often not identical for a given angiographic projection. The aim of this study was to quantify the magnification error (out-of-plane magnification error) for the major coronary artery segments imaged in frequently used angiographic projections. Methods The intrathoracic spatial location of 468 coronary segments (RCA 196, LAD 156, LCX 116) and their respective coronary catheters were established with biplane angiography and known imaging geometry data. The error in the radiographic magnification or calibration factor was then calculated for all 936 monoplane projections using the spatial coordinates and imaging geometry data. Results The mean magnitude of magnification error was 4% within all 936 measurements. The magnitude and direction of error varied with the lesion localization and the angiographic projection angle (range −12.6% to +10.6%). The error characteristics could be described with six typical error groups by stratifying the data according to the three main coronaries and two angiographic planes. In 24% of measurements, the magnification error exceeded the 5.2% error limit acceptable for reference vessel sizing. Measurements of left coronary arteries were mainly affected by it. Conclusion: The magnification error contributes to the calibration error in measuring arterial dimensions by quantitative angiography. This error may affect the reliability of clinical studies and the proper sizing of interventional devices. These findings could be used to improve current error correction algorithms in order to reduce the effect of the magnification error in measuring arterial dimensions.

Die Verkürzungsdarstellung: ein neues Verfahren zur räumlichen Interpretation und Bewertung der Sicht auf das interessierende Koronarsegment

Bei der biplanen Koronarangiographie erreicht der Untersucher häufig empirisch keine verkürzungsfreie Darstellung des interessierenden Koronarsegments. Die visuelle Beurteilung des Koronarangiogramms kann dadurch für jede Projektionsebene zu diskrepanten Ergebnissen führen. Eine Möglichkeit zur räumlichen Interpretation und Bewertung der Sicht auf das interessierende Koronarsegment könnte deshalb die Entscheidungsfindung während interventioneller Prozeduren wesentlich unterstützen. Wir entwickelten mit der Verkürzungsdarstellung ein einfaches Verfahren, das in jeder Projektionsebene den räumlichen Gefaßverlauf und dessen projektive Verkürzung anzeigt.

DIFFERENZIERUNG ZWISCHEN VITALEM HERZMUSKELGEWEBE UND INFARKTNARBE MITHILFE DER MAGNETOKARDIOGRAPHIE

Magnetocardiography provides touchless Information about myocardial excitation propagation and repolarization. This evolving diagnostic technique hos been usedsofar to risk-stratijy patients in terms ofsudden cardiac deaih and to detect myocardial ischemia. We evaluated its potential to assess myocardial viability in patients with coronary artery disease. Magnetocardiography was performed using a shielded prototype 49-channel LTS SQÜID System. A specißc algoritkm was developed to calculate automaticfy a sei ofmagnetocardiographicparameters. Regional myocardial viability was determined using F-labeledfluoro-2-deoxyglucosepositron emission tomography. We found that magnetocardiography may contribute essentialfy to discriminate between viable myocardium and infarct scar. Keywords—FDG, magnetocardiography, myocardial viabilityf positron emission tomography, SQUID

UNTERSTÜTZUNG DER PRIMÄREN STENTIMPLANTATION DURCH ANGIOGRAPHISCHE LÄNGENMESSUNG

In this study a procedure for online measurement of a coronary segment length during primary stenting is presented. The spatial segmental axis is calculated from a biplane angiogram and the corresponding projection data by simple delineation of the proximal and distal segment sites in each image. In a clinical evaluation the length error, projectional foreshortening and time frame during measurement of 222 stents or carrier balloons were calculated. The overall percentage length error was 3.3(+)-2.4%. The device length imaged with a mean projectional foreshortening of 18(+)-20% was measured within 18(+)-4 s. The procedure yields the accurate length of coronary segments within a short computation time taking projectional foreshortening into account.