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Dive into the research topics where Hans A. Verheul is active.

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Featured researches published by Hans A. Verheul.


Heart | 1999

To operate or not on elderly patients with aortic stenosis: the decision and its consequences

Berto J. Bouma; R. B. A. van den Brink; J van der Meulen; Hans A. Verheul; Emile C. Cheriex; Hans P.M. Hamer; Egbart Dekker; K. I. Lie; Jan G.P. Tijssen

OBJECTIVE To evaluate the application of guidelines in the decision making process leading to medical or surgical treatment for aortic stenosis in elderly patients. DESIGN Cohort analysis based on a prospective inclusive registry. SETTING 205 consecutive patients (⩾ 70 years) with clinically relevant isolated aortic stenosis and without serious comorbidity, seen for the first time in the Doppler-echocardiographic laboratories of three university hospitals in the Netherlands. RESULTS The initial choice was surgery in 94 patients and medical treatment in 111. Only 59% of the patients who should have had valve replacement according to the practice guidelines were actually offered surgical treatment. These were mainly symptomatic patients under 80 years of age with a high gradient. Operative mortality (30 days) was only 2%. The three year survival was 80% in the surgical group (17 deaths among 94 patients) and 49% in the medical group (43/111). Multivariate analysis showed that only patients with a high baseline risk, mainly determined by impaired left ventricular function, had a significantly better three year survival with surgical treatment than with medical treatment. CONCLUSIONS In daily practice, elderly patients with clinically relevant symptomatic aortic stenosis are often denied surgical treatment. This study indicates that a surgical approach, especially where there is impaired systolic left ventricular function, is associated with better survival.


American Journal of Cardiology | 1993

Effects of changes in management of active infective endocarditis on outcome in a 25-year period

Hans A. Verheul; Renee B.A. van den Brink; Tom van Vreeland; Adrian C. Moulijn; Donald R. Düren; Arend J. Dunning

The clinical outcome and long-term follow-up of 130 consecutive patients (141 episodes) with active infective endocarditis who were treated between 1966 and 1991 were analyzed. There was a shift toward a higher proportion of referred patients (39 to 78%), patients aged > 60 years (11 to 41%) and urgent surgical treatment (11 to 44%). Medical treatment was administered in 98 patients (70%); 30-day mortality was 27%. Surgery was performed in 43 patients (30%), with an operative mortality of 26%; 9 of 14 patients (64%) who underwent operation within the first week of admission died. Patients with severe heart failure are at the highest risk for early mortality (relative risk = 21.1; 95% confidence interval 7.4-60.3). Referred patients were much more often treated surgically than were nonreferred patients (48 versus 14%) and had a lower operative mortality (24 vs 30%). Nonreferred patients were more often treated medically (86 vs 52%) and with lower mortality (19 vs 39%). The total follow-up time was 730 patient-years; only 1 patient was considered lost to follow-up. The overall cumulative 5-year and 10-year survival after hospital discharge for patients after urgent surgery were 84 +/- 7% and 53 +/- 7%, respectively, and for those after medical treatment 84 +/- 5% and 77 +/- 6%, respectively. The probability of remaining free of late events (recurrent endocarditis, late valve replacement or death) during 5 and 10 years for patients after urgent surgery was 84 +/- 7% and 53 +/- 15%, respectively, and for those after medical treatment 59 +/- 6% and 40 +/- 7%, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)


The Lancet | 1993

Background mortality in clinical survival studies

Hans A. Verheul; Egbart Dekker; Arend J. Dunning; Adrian C. Moulijn; P. M. M. Bossuyt

In long-term follow-up studies of survival after an initial event (eg, an operation) mortality from causes other than the one under study obscures the results, especially in elderly patients. In the traditional approach to the calculation of expected mortality a fictitious cohort is drawn from the general population, being matched for age, sex, and calendar time at the time of the initial event. The membership of this cohort is then kept constant from the initial event until the closing date of the study. The survival and mortality of this static cohort is then compared with that of the dynamic patient cohort to throw light on mortality from extraneous causes. This method can lead to severe bias if there is a strong correlation between the duration of observation of the patients and their age. The analysis can be improved by applying rate adjustment when calculating the background component of mortality. In this approach mortality rates from the general population are adjusted (weighted) so that the age, sex, and calendar year are at all times identical with those of each of the patients still alive and under observation. This is illustrated by means of a simplified example and a real-life one from a study at survival after aortic valve replacement. Estimation of rate-adjusted background mortality provides a framework that may put long-term survival, especially of elderly patients, in proper perspective.


American Journal of Cardiology | 1991

Late results of 200 repeat coronary artery bypass operations.

Hans A. Verheul; Adrian C. Moulijn; Sjoerd Hondema; Michiel Schouwink; Arend J. Dunning

To determine the clinical outcome and the long-term results of a second coronary artery bypass operation, we studied preoperative clinical status and catheterization data in 200 consecutive patients over a 9-year period (1979 to 1987) (mean follow up time 34 months, maximum 120). The study group included 169 men and 31 women (mean age 58.4 years [7% greater than 70 years]). Sixty-four percent of patients had severe angina (New York Heart Association class IV), 70% had 3-vessel coronary artery disease and 21% had poor left ventricular function. Reoperation was performed after a mean interval of 58 months after the first procedure. A mean of 3.3 distal anastomoses was placed. The operative mortality rate (30 days) was 7.5%, with additional cardiac morbidity (myocardial infarction, heart failure) in 11.5% of patients. Multivariate analysis showed an increased risk in women (risk ratio 3.6) and in patients with poor left ventricular function (risk ratio 3.1). The cumulative 5-year survival rate was estimated at 84%, with a rate of 77% for patients with poor left ventricular function (difference not significant). The probability of remaining free of a cardiac-related event (myocardial infarction, angioplasty, third operation, cardiac death) was 64% for 5 years. At the end of follow-up, 79% of the surviving patients were in New York Heart Association class I or II and nearly 50% of patients in the fifth year after the reoperation had good functional status. It is concluded that a reoperation is effective but carries an increased, immediate, operative risk.(ABSTRACT TRUNCATED AT 250 WORDS)


Journal of The American Society of Echocardiography | 1991

Long-Term Reproducibility of Conventional Doppler Analysis in Patients With Prosthetic Valves

Renee B.A. van den Brink; Hans A. Verheul; Frans J.L. van Capelle; Cees A. Visser; Arend J. Dunning

Long-term reproducibility of Doppler recordings made by the same investigator using the same ultrasound equipment was determined in 50 clinically stable patients. The mean interval between the first and second examination was 16 +/- 7 months. In 90% of the 33 patients with aortic prostheses, the relative difference between the first and second examination was less than 16% (mean value 9.1%) for the maximum instantaneous gradient and less than 17% (mean value 7.4%) for the mean gradient; the relative difference was less than 20% (mean value 8.5%) for the maximum flow velocity in the left ventricular outflow tract and less than 24% (mean value 10.8) for the maximum flow velocity ratio. In 90% of the 25 patients with mitral prostheses, the absolute difference between the first and second examination was less than 3 mmHg for the maximum instantaneous gradient, less than 2.5 mmHg for the mean gradient, and less than 20 msec for the pressure half-time. We conclude that long-term reproducibility of Doppler echocardiographic characteristics of prosthetic valve function is good as far as transprosthetic gradients or pressure half-time are concerned but is less so for maximum flow velocity in the left ventricular outflow tract and the maximum flow velocity ratio. Changes beyond the aforementioned values may represent a real change in prosthetic valve function.


Journal of the American College of Cardiology | 1995

Analysis of risk factors for excess mortality after aortic valve replacement

Hans A. Verheul; Renee B.A. van den Brink; Berto J. Bouma; Gerard Hoedemaker; Adrian C. Moulijn; Egbart Dekker; Patrick M. Bossuyt; Arend J. Dunning


American Journal of Cardiology | 1992

Value of exercise Doppler echocardiography in patients with prosthetic or bioprosthetic cardiac valves

Renee B.A. van den Brink; Hans A. Verheul; Cees A. Visser; Mark J.W. Koelemay; Arend J. Dunning


Circulation | 1998

EFFECT OF AGE ADJUSTMENT IN PREDICTING OUTCOME. AUTHORS' REPLY

R. B. A. van den Brink; Egbart Dekker; Hans A. Verheul; Jan G.P. Tijssen; M. Enriquez-Sarano; K. R. Bailey


Circulation | 1998

Effect of age adjustment in predicting outcome

Renee B.A. van den Brink; Egbart Dekker; Hans A. Verheul; Jan G.P. Tijssen


Nederlands Tijdschrift voor Geneeskunde | 1998

Rapportcijfers voor de hartchirurg; validiteit van waargenomen verschillen in sterfte

Egbert Dekker; Hans A. Verheul; R. B. A. van den Brink; Adrian C. Moulijn

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Cees A. Visser

VU University Medical Center

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K. R. Bailey

University of Amsterdam

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