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H W Plokker

Publications and source records attributed to H W Plokker.

11 recordsLinked to original sources
PubMed1992

[Are the long-term results of venous aortocoronary bypass procedures really so bad? A prospective 13-year-long study of 428 patients].

OBJECTIVE: To assess the long-term results of coronary surgery using venous bypasses. DESIGN: Prospective study. SETTING: St. Antonius Hospital, Nieuwegein, the Netherlands. METHOD: In 446 successive patients subjected to coronary surgery between 1 April 1976 and 1 April 1977, a complete long-term follow-up study was carried out after an average of 11.5 years (1.5 months-14.3 years). RESULTS: The peroperative mortality was 3%, a peroperative myocardial infarction occurred in 6.3% and complete revascularization was achieved in 77.6% of the patients. In 90 of 100 patients selected at random, cardiac catheterization was performed 13.5 months on average after the operation. The patency of the single grafts was 89.8%, that of the side-to-side and end-to-side anastomoses of the sequential grafts was 90.4% and 83%, respectively. Mortality, myocardial infarction, necessity of a second operation and angina pectoris occurred with low frequency during the first five years after the operation. Subsequently, complications increasingly occurred. Ten years after the operation 18.8% of the patients had died, 11.9% had suffered a myocardial infarction, 13.4% had been subjected to a second operation and 6.4% to balloon angioplasty, while 46.4% had once more developed angina pectoris. Thirteen years after the operation 29% of the patients had remained completely free from cardiac problems. CONCLUSION: Although arterial bypasses have been increasingly used in recent years, an indication for the use of venous transplants will continue to exist in the future, also, for certain groups of patients (those younger than 50 or older than 75 years). Our study clearly shows that with venous bypasses, also, satisfactory long-term results can be obtained.

Actuarial Analysis↗
PubMed1992

Initial and long-term results of percutaneous transluminal coronary angioplasty in patients 75 years of age and older.

In 212 patients aged 75 years and older the immediate and long-term results of percutaneous transluminal coronary angioplasty (PTCA) were assessed. For 293 stenoses the primary angiographic success rate was 96% and the overall clinical success rate was 90.6%. Angioplasty caused a myocardial infraction in 7 patients (3.3%), 2 patients (0.9%) needed emergency aorto coronary bypass surgery, and 4 patients (1.9%) died following the procedure. Actuarial 7 year survival was calculated at 69.3% with a standard deviation (SD) of 8%. Actuarial cardiac survival at 7 years was 92.1% (SD 3%), whereas non-cardiac survival at 7 years was 75.3% (SD 9%). Actuarially, at 7 years 98.5% (SD 1%) were estimated to remain free from myocardial infarction in the angioplasty-related area, 95.7% (SD 2%) to remain free from any myocardial infarction, 93.9% (SD 2%) to remain free from re-PTCA because of a recurrence, 84.7% (SD 5%) to remain free from any re-PTCA, and 97.1% (SD 2%) to remain free from (re)-operation. Fifty-two point three percent (SD 8%) were estimated to remain free from any cardiac event. If recurrence of angina is taken into account, only 25.8% (SD 13%) remain asymptomatic during 7 years follow-up. After successful angioplasty in patients aged 75 and older the chance of remaining free from any event or angina at 7 years actuarial follow-up gets as low as 15.7% (SD 9%). We conclude that in selected elderly patients angioplasty can be performed with a high success rate, although the periprocedural mortality and morbidity appear to be higher than in the younger age group. During long-term follow-up, most of the patients remain free of cardiac events and survival appears to be largely dependent on noncardiac factors. However, long-term relief from angina is probably less than in younger patients.

Actuarial Analysis↗
PubMed1992

Endocarditis on a left atrial myxoma.

A 55-year-old woman presented with fever and malaise. Three blood cultures were positive for Streptococcus sanguis. A diagnosis of endocarditis was made and the patient was treated with intravenous penicillin and gentamicin. Endocardiography revealed a large left atrial tumour. At operation a myxoma covered by deposits of fibrin was excised. Microscopy revealed massive infiltrates of neutrophils and remnants of bacteria, indicating that this myxoma was a nest for infection.

Endocarditis, Bacterial↗
PubMed1991

The Dutch experience in percutaneous transluminal angioplasty of narrowed saphenous veins used for aortocoronary arterial bypass.

Of 19,994 percutaneous transluminal coronary angioplasty procedures performed in The Netherlands between April 1980 and January 1989, the long-term follow-up of 454 patients who underwent angioplasty of greater than or equal to 1 saphenous vein bypass graft was reviewed. In 46% of patients single graft angioplasty was attempted, and in 54% of patients sequential graft angioplasty was attempted. The clinical primary success rate was 90%. In-hospital mortality was 0.7%, 2.8% of patients sustained a procedural myocardial infarction, and 1.3% of patients underwent emergency bypass surgery. After a follow-up period of 5 years, 74% of patients were alive, and 26% were alive and event-free (no myocardial infarction, no repeat bypass surgery or repeat angioplasty). In patients in whom the initial angioplasty attempt was unsuccessful, only 3% were event-free at 5 years, versus 27% of successfully dilated patients. The time interval between the angioplasty attempt and previous surgery was a significant predictor for 5-year event-free survival. The event-free survival rates for patients who had bypass surgery 1 year before, between 1 and 5 years, and 5 years before angioplasty, were 45, 25 and 19%, respectively. Less than one-third of patients with previous bypass surgery who had angioplasty of the graft remained event-free after 5 years. In patients needing angioplasty within 1 year after bypass surgery, better long-term results were achieved.

Angioplasty, Balloon, Coronary↗
PubMed1990

Percutaneous recanalization of chronic total coronary occlusions: experience with the direct argon laser assisted angioplasty system (LASTAC).

The present study reports initial experience with the argon laser LASTAC system in patients with chronic coronary artery occlusion not amenable to recanalization with conventional systems. The LASTAC system conducts focused argon laser light through an optical fiber of 200 microns which is inserted through a multiple-lumen balloon catheter. The balloon serves the purpose of coaxially positioning the optical fiber. The balloon catheter is advanced by means of a guidewire to about 2 mm proximal to the occlusive lesion. After advancing the optical fiber, in three times 10 to 20 Joules are applied. Thereafter, the optical fiber is withdrawn, the balloon deflated, the catheter system repositioned and the sequence repeated. The integrity of the system with respect to temperature increase, energy loss and contact with tissue is monitored with lens fluorescence. In 29 patients with angina pectoris and documented ischemia, 30 complete occlusions were treated. In 18 (60%), there was successful recanalization with conventional balloon dilation thereafter. The total success rate for the right coronary artery was 55%, for the circumflex artery 71% and for the left anterior descending artery 67%. With regard to complications, in one patient there was nontransmural myocardial infarction, in seven there were asymptomatic dissections, one patient required defibrillation. The value of the LASTAC system for recanalization of chronically occluded coronary arteries has not yet been fully delineated. However, the success rate of 60% in previously treatment-refractory patients as well as the fact that no perforations were incurred, is encouraging. Further assessment will require analysis of long-term results as well as comparison of other methods.

Adult↗
PubMed1989

Left atrial and right ventricular cardiac myxoma. A case report.

A case is presented with a tumour in the left atrium as well as in the right ventricle. During the initial investigation of the atrial myxoma, the ventricular tumour was overlooked and a second operation was necessary. Once the diagnosis of myxoma is made, a second synchronous tumour should always be carefully sought.

Diagnosis, Differential↗
PubMed1977

A computer program for ECG classification according to the Minnesota code.

A program for the automated generation of Minnesota-codes from the standard 12-lead electrocardiogram (ECG) recorded at rest has been developed. The program has been written as a part of the Modular TNO ECG/VCG Processing System. Results of the program on two sets of ECG'S (279 predominantly normal recordings and 286 consecutive recordings from a Cardiological Department) are presented. These electrocardiograms were also coded by hand by different ECG technicians. An agreement of 83% between hand and computer coding was obtained. One-third of the disagreements (6% of the cases) is caused by small differences (less than 5%) in the measurements between technicians and computer.

Diagnosis, Computer-Assisted↗
PubMed1975

Aneurysm of a pulmonary artery branch: an uncommon cause of a coin lesion.

We report the case of a 26-year-old woman with ventricular septal defect associated with a typical coin lesion as shown on the chest roentgenogram. Selective angiography revealed the coin lesion to be caused by an aneurysm of a tertiary pulmonary arterial branch. In addition, two smaller aneurysms were noted. It is postulated on clinical and histologic grounds that the aneurysms were caused by congenital weakness of the pulmonary arterial wall in conjunction with increased pulmonary flow and slightly elevated pulmonary arterial pressure.

Adult↗