Stella Muurling

COAGULATION ACTIVATION IN PATIENTS UNDERGOING DIRECTIONAL CORONARY ATHERECTOMY

Restenosis is a major problem of percutaneous transluminal coronary angioplasty (PTCA) and related procedures. To better understand the underlying pathophysiologic mechanisms, coagulation and fibrinolytic variables were analysed prospectively in 35 patients after directional coronary atherectomy (DCA) and in 20 control patients undergoing diagnostic heart catheterisation and coronary angiography. Blood samples were taken before and 1 h, 24 h and 48 h after the procedure. No subacute thrombosis or unstable angina were documented in any patient. In 8 out of these 35 patients late restenosis was diagnosed during follow-up angiography 3-6 months after DCA. In these 8 patients prothrombin fragments (F1 + 2) rose from 0.7 to 0.9 nmol/l (P < 0.01) and thrombin-antithrombin III complexes (TAT) from 2.9 to 6.0 micrograms/l (P < 0.01), but not significantly in 27 patients without restenosis and in the control patients. In patients with late restenosis plasminogen activator inhibitor (PAI-1) also increased from 2.4 to 4.9 U/ml (P < 0.05) 24 h after DCA while there were no significant changes in patients without restenosis and in control patients. D-Dimer/TAT ratio reflecting the balance between clotting activation and fibrinolysis was significantly lower after 24 h in restenosis patients. The findings suggest that coagulation activation and hypofibrinolysis during 48 h after DCA might be associated with the development of late restenosis.

Detection of diastolic dysfunction: acoustic quantification (AQ) in comparison to Doppler echocardiography

Objectives. To evaluate the potential of acoustic quantification (AQ) in detection of diastolic dysfunction in comparison to Doppler analysis, we investigated, as a model of restrictive filling pattern, nonrejecting heart transplant recipients early postoperatively. Background. AQ, an ultrasonic backscatter imaging system, enables inst-antaneous calculation of cavity areas and thus provides a new approach to diastolic function. Methods. Of 27 pts who have undergone heart transplantation, echocardiography has been performed at the day of biopsy. During a time course of 8 weeks echocardiographic data have been analysed at 3 different time points (early, mid and late) in 16 nonrejecting pts. Indexes of the area-change waveform and its 1. derivative (dA/dt) obtained by AQ were opposed to usual Doppler indexes. Results. In comparing data of the early and late time point of investigation, significant changes of early diastolic filling were detectable by AQ as well as by Doppler: End-diastolic areas have increased (p<0.001), while peak filling rate (p<0.0001), slope of area change during rapid filling (p<0.001) and amount of relative area change during rapid filling (p<0.001) have decreased. Complementary, Doppler derived pressure half-time (p<0.0001) and isovolumic relaxation time (p<0.0001) have increased while the peak early filling velocity (p<0.0001) and its time velocity integral (p<0.001) have decreased. Conclusion. An initial restrictive filling pattern has improved 8 weeks postoperatively. Since multiple indexes, obtained from the area change waveforms, in particular the for end-diastolic area normalized peak filling rate, seem to be highly sensitive in detecting changes of diastolic function, AQ may play an important complementary role in non-invasive evaluation of restrictive filling pattern.

Dynamic on-line quantification of biventricular function with acoustic quantification (AQ)

Objectives. Acoustic quantification (AQ), a recently developed ultrasonic integrated backscatter imaging system providing on-line measurements of ventricular cavity areas and their functional indexes, was validated in comparison to angiography and Doppler derived systolic dP/dt. Normal AQ-reference values were established. Methods and Results. 1. In 45 patients undergoing heart catheterization, AQ derived areas in end-diastole (EDA), end-systole (ESA) and the resulting fractional area change (FAC) in apical 2- and 4-chamber view were compared to the corresponding biplane angiographic data. All correlations yielded significant values (p<0.0001; EDA: r=0.90, SEE=2.6 cm2; ESA: r=0.91, SEE=2.2 cm2; FAC: r=0.90, SEE = 4.1%). However, AQ-areas were underestimated by about 25%. 2. In 36 patients with mitral regurgitation AQ-FAC and AQ derived systolic dA/dt were compared to the Doppler derived systolic dP/dt, yielding significant correlations with r=0.91 and r=0.87; p<0.0001. 3. In 50 healthy subjects, AQ derived EDA, ESA and FAC averaged 25.7 ± 4.9, 14.7 ± 3.3 cm2 and 43.2 ± 4.8% for the left, and 17.1 ± 3.8, 9.0 ± 2.9 cm2 and 47.3 ± 9.2% for the right ventricle. For EDA normalized peak filling (PFR) and ejection rates (PER) yielded 2.7 ± 0.28 and -2.4 ± 0.42 EDA/sec for the left and 3.4 ± 0.74 and -2.9 ± 0.62 EDA/sec for the right ventricle. The interobserver and day-to-day variability of AQ in healthy subjects and cardiac patients was low for EDA, ESA and FAC (<12%) and higher for PFR and PER (<20%). Conclusion. In comparison to angiography AQ reliably quantitates on-line left ventricular fractional area change, although AQ- areas are underestimated. AQ offers reproducible values of systolic and diastolic function and a new approach to cardiac patients.

Endomyokardbiopsie – Hilfreich in der Differentialdiagnostik zwischen Myokarditis und dilativer Kardiomyopathie

In der Differentialdiagnose zwischen Myokarditis und dilativer Kardiomyopathie ist die Endomyokardbiopsie ein wesentlicher Untersuchungsbestandteil geworden. Anhand wichtiger immunhistologischer Befunde gelingt oft die sichere Diagnosestellung. Therapie und damit weiterer Verlauf sind von einer frühen Diagnose abhängig. Wir berichten über einen 44jährigen Patienten, der mit dem echokardiographischen Bild einer dilativen Kardiomyopathie zur invasiven kardiologischen Diagnostik in unsere Klinik kam. Es erfolgte zusätzlich eine Endomyokardbiopsie, die den Zufallsbefund einer floriden Myokarditis erbrachte. Nachdem sich bis zur Wiederaufnahme eine dramatische Verschlechterung des Gesundheitszustandes ergeben hatte, wurde neben einer symptomatischen Therapie zusätzlich mit einer Kombination aus Prednisolon, Azathioprin und humanem Immunoglobulin G behandelt, welche zu einer deutlichen Besserung der Beschwerden mit beitrug. Ein großzügiger Einsatz der Endomyokardbiopsie scheint empfehlenswert, da dieses diagnostische Verfahren auch therapiebestimmend sein kann. Endomyocardial biopsy is an established technique to distinguish between myocarditis and dilated cardiomyopathy. Even when clinical symptoms for myocarditis are lacking, immunohistologic findings may establish a clear diagnosis. For treatment, however, an early diagnosis is mandatory. We report on a 44 year old patient who was admitted with the echocardiographic diagnosis of dilated cardiomyopathy. He underwent diagnostic angiocardiography and endomyocardial biopsy. The latter demonstrated an active myocarditis. At the time of readmission, 2 weeks later, the patient had deteriorated. Now, additional to a symptomatic therapy, prednisolone, azathioprine and human immunoglobulin G were given and patient conditions improved dramatically. The use of endomyocardial biopsy seems recommendable in order to define patients diagnosis and their results may be necessary to decide patients therapy.

Frühpostoperative Flußreservebestimmung in Arteria Mammaria Grafts mittels miniaturisierter intravasaler Dopplertechnik

In der koronaren Bypass-Chirurgie werden zunehmend auch die rechte (RIMA) und die linke (LIMA) Arteria mammaria interna verwendet (1). Von ihnen ist bekannt, daß sie sich im Gegensatz zu anderen Gefäßen auch über Jahre nicht arteriosklerotisch verändern. Zudem weisen sie ein annähernd gleiches Kaliber wie die zu versorgenden Koronargefäße auf und sie behalten ihre Vasa vasorum. Eine bislang ungeklärte Frage war, ob RIMA und LIMA bereits kurz nach der Operation und besonders auch in Belastungssituationen ausreichend Blut zur Koronarperfusion zur Verfügung stellen können. ERGEBNISSE

Verteilung des Blutflusses in normalen Koronararterien - Messungen mittels miniaturisierter Dopplertechnik

Die Frage, ob sich der Blutfluß innerhalb einer verzweigten menschlichen Koronararterie mit gleichmäßiger oder unterschiedlicher Geschwindickeit ausbreitet, wird kontrovers diskutiert. Bisherige Ergebnisse, die mit einem 3 French MilarDopjpler-Katheter erzielt wurden, legten den Schluß nahe, daß die Ausbreitung des Blutflusses zumindest in den proximalen Abschnitten gleich ist (1). Die Größe der Katheter ließen jedoch ein weiteres Vorgehen nach distal nicht zu. Neuere Untersuchungen mit einem dünneren Dopplerdraht hatten im Vergleich zu den 3 F-Kathetern gezeigt, daß bei Gefäßdurchmessern ab 1,5 mm eine sehr gute Korrelation besteht (2). ERGEBNISSE