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G Helft

Publications and source records attributed to G Helft.

67 records · Page 4Linked to original sources

[Factors determining the improvement of effort capacity in aged patients with coronary disease during the 1st month following coronary surgery].

UNLABELLED: In order to determine the predictive factors of improvement of the physical capacity of elderly coronary patients following coronary surgery, we retrospectively analysed the data of 204 consecutive patients over the age of 65 years (181 men, 23 women, mean age: 70 +/- 4.4 years), admitted for a phase II active training programme. METHODS: The patients were divided into two groups as a function of the rate of improvement of the duration of the stress test: group A (improvement greater than or equal to 25%; n = 108) and group B (less than 25%; n = 96). Comparison of these 2 groups by multivariate analysis identified predictive factors of improvement among seven variables: age, sex, excess weight, haemoglobin, number of training sessions, duration of baseline stress test, interval between bypass graft and start of training. RESULTS: After training, the duration of the stress test and the maximal power were improved by 26.5% and 24%, respectively: 7.1 +/- 1.7 vs 8.9 +/- 2.3 minutes (p = 0.0001); 79 +/- 18.4 vs 97.8 +/- 23.7 watts (p = 0.0001). 34 (1.4%) of the 2,396 training sessions were temporarily interrupted, because of muscle fatigue in 47% of cases. Patients who had readapted before the 15th postoperative day presented fewer incidents: 4.3% vs 13.1%; NS. Only three variables appeared to be predictive of improvement of physical capacity: a duration less than 6 minutes on the baseline stress test (p = 0.0003), more than 12 training sessions (p = 0.0029) and age less than or equal to 70 years (p = 0.014). CONCLUSION: In elderly subjects undergoing coronary surgery, the improvement of physical capacity is greater the lower the baseline effort, the lower the age-group and the greater the number of training sessions. In the absence of contraindication, it appears justified to include elderly coronary patients in training programmes, even when their baseline effort level appears to be low. This training can be started by the 15th postoperative day.

Age Factors↗

[Rehabilitation of aged patients with bicycle ergometer after coronary surgery].

This study was undertaken to assess the contraindications to rehabilitation by exercise testing on a bicycle ergometer and the tolerance of this procedure in elderly patients recovering from coronary surgery. One hundred and eighty-four patients aged over 65 years were included (Group I). The rehabilitation program consisted of exercise testing on admission period. The results were compared with those of 146 patients aged 65 or less (Group II). Twenty-six per cent of the elderly patients had a contraindications to this type of rehabilitation compared with only 4.8% in Group II. The main contraindications were extracardiac (21.7%), including infectious causes (4.3%), neuropsychiatric (3.3%), respiratory (2.7%) and rheumatological conditions (2.2%). Cardiac causes represented only 4.3% of the contraindications. In the patients undergoing the training program, the maximum power and the duration of exercise testing increased respectively from 81 +/- 17 to 97 +/- 21 watts (+21% ; p < 10(-3)) and 7 +/- 1.7 to 9 +/- 2 minutes (+28.6%, p < 10(-3)). The change in these parameters was comparable in the other group: 94.5+/- to 118 +/- 26 watts (+24.8% ; p < 10(-3)) and 8.5 +/- 1.9 to 10.9 +/- 2.4 minutes (+28.2% ; p < 10(-3)). On the other hand, the rate-pressure product decreased slightly in the elderly patients (-5.5% ; p = 0.07, compared with -13% in Group II, p = 0.001). Complications were rare: 1.6% of temporary interruption of a session (versus 0.6%). No serious complications were observed. The authors conclude that, after coronary surgery, the majority of elderly coronary patients can participate in physical training programs on bicycle ergometers without major complications. In the absence of contraindications, patients, and even elderly patients, should be encouraged to enroll for these programs after coronary bypass surgery.

Aged↗

Bioprosthetic valve replacement in the elderly.

One hundred and ten patients aged more than 65 years (mean, 73.4; range, 65-82) underwent successful bioprosthetic valve replacement (aortic, n = 71; mitral, n = 32; both, n = 7) from 1979 to 1985. The valve was pericardial in 39 cases and porcine in 78. The mean follow-up was 75 months (total, 688 patient-years; range, 2 months to 12 years). Actuarial patient survival was 79.4% at 5 years and 55.2% at 10 years. Thirty-seven patients died: 18 from valve-related causes and 19 from other causes. Eight patients have been reoperated on for valve-related complications (1.17% per patient-year): five primary deteriorations, two paravalvular leaks and one case of endocarditis. One surgical death occurred (12.5%). Twenty-five percent of the patients were receiving anticoagulants because of atrial fibrillation, and 5.4% developed severe bleeding (3.8% patient-year). Mid-term follow-up of these patients aged more than 65 years and undergoing bioprosthetic valve replacement surgery revealed a low rate of documented primary structural deterioration (0.9% per patient-year), a low mortality rate on reoperation (12.5%) and a high mortality rate due to non valve-related causes (51.4%).

Aged↗

[Current biological surveillance of oral anticoagulant treatment].

The prothrombin time is the coagulation time of citrated plasma in the presence of calcium and a tissue extract, thromboplastin, added in excess. The prothrombin time was historically the first method of evaluation and control of oral anticoagulation. Over the years, the different thromboplastins have changed, diversified, so affecting the result of the prothrombin ration established from the prothrombin time and a reference curve. In 1985, the International Committee on Thrombosis and Haemostasis requested that all the losts of thromboplastin have their international sensitivity index (ISI) indicated. This allowed uniformity of the results by the introduction of the INR (International Normalized Ratio) calculated by the formula: INR = (PTR)ISI, the PTR or prothrombin time ratio corresponding to the patients' prothrombin time divided by that of reference control plasma. It is, in fact, impossible to interpret the results of a prothrombin ration without knowing their expression in INR. The consequences of the absence of uniformity in the control of anticoagulant therapy are important and serious. The uncertainty concerning the degree of anticoagulation inherent in the use of a single prothrombin ratio may be the source of bleeding or thromboembolic complications. Curiously, the system based on the INR is neither generalised, nearly 10 years after its recommendation, nor adopted by the majority of practitioners. However, the stakes are high because the principal complication of oral anticoagulants remains bleeding, including the dramatic strokes. Moreover, the global mortality due to haemorrhagic complications is about 0.1 to 0.5% for treatments of short duration and much higher in prolonged therapy.(ABSTRACT TRUNCATED AT 250 WORDS)

Administration, Oral↗

[Influence of post-infarction myocardial revascularization on the prevalence of delayed potentials].

It has been shown that the presence of ventricular late potentials is a predictive factor of ventricular tachycardia and sudden death after myocardial infarction. The value of thrombolysis in the reduction of the prevalence of ventricular late potentials is now well established. However, the effects of other modes of revascularisation is less well known and more controversial. The authors undertook a retrospective study of 139 consecutive patients undergoing coronary angiography after primary myocardial infarction. The presence of ventricular late potentials fulfilling two of the three usual criteria was sought after a revascularisation procedure. The overall prevalence of ventricular late potentials was 30.9%. This was not affected either by the site of infarction of by the single or multiple character of the coronary artery disease. In addition, the left ventricular ejection fraction was not significantly different in patients with positive ventricular late potentials compared with the others. On the other hand, revascularisation of the culprit lesion responsible for the infarction was strongly correlated with a lower incidence of ventricular late potentials (p < 10 (-5)). In particular, the different incidence of positive late potentials between the dilated (9.3%) and non-dilated group (49.2%) was statistically significant (p < 10 (-6)) without any correlation to the single or multiple character of the coronary disease. The authors discuss the different reports in the literature concerning the effects of angioplasty and coronary bypass surgery on the incidence of ventricular late potentials. Conclusion; the review of the literature shows that thrombolysis significantly reduces the incidence of late potentials after myocardial infarction and the present study suggests that angioplasty and coronary bypass surgery may also be effective.

Arrhythmias, Cardiac↗

[Effects of thrombolysis on platelets and coagulation].

Rupture of an atherosclerotic plaque is often the trigger of the clotting process, via the activation of platelets which immediately adhere, aggregate and initiate coagulation on their surface. The final step of platelet aggregation involves membrane glycoprotein IIB-IIIA which has become available. Antibodies directed against this membrane receptor are currently under evaluation. They possess definite antithrombotic properties. Complex interactions between thrombolysis, leading to generation of plasmin, and platelet functions have been identified. Depending on its concentration and possibly successively, and according to in vitro experimental conditions, plasmin may be a platelet proaggregant or antiaggregant. Correlations have also been recently demonstrated between thrombolytic activity and coagulation, as, paradoxically, it has been shown that plasmin, the final step of thrombolysis, activates the intrinsic pathway of coagulation, predisposing to the formation of thrombin. This activation is involved in the efficacy of heparin therapy following intravenous thrombolysis during the acute phase of myocardial infarction. This paradoxical action of thrombolysis could also play a role in reocclusions after effective thrombolysis during the acute phase of myocardial infarction. A better understanding of the thrombolysis process and its interactions with platelets and coagulation is important in order to improve the results of this treatment, which are correlated with patient survival.

Blood Coagulation↗

Human anti-streptokinase antibodies induce platelet aggregation in an Fc receptor (CD32) dependent manner.

Exposure to streptokinase (SK) elicits anti-SK antibodies (Abs), which inhibit fibrinolysis and induce platelet aggregation. The mechanism of the latter is not fully understood, although it seems to involve platelet binding by a plasminogen streptokinase and anti-SK ternary complex. Anti-SK Abs were purified by affinity chromatography from serum of patients having received SK for acute myocardial infarction (AMI), and were shown to be of the IgG type. Their effects were studied with (i) human platelets in citrated plasma in the presence of SK or acetylated plasminogen-SK activator complex (APSAC), and (ii) in washed platelets, resuspended in Tyrode buffer after lowering the ionic strength, in the presence of APSAC (which provides both SK and plasminogen). An antibody concentration-response curve was obtained, showing a plateau in the presence of 0.1 mg/ml IgG. By increasing the concentration of APSAC, we obtained a unimodal response curve, the optimal concentration of APSAC being 0.05 U/ml. Aggregation was suppressed by chelating calcium with EDTA, blocking fibrinogen binding by the synthetic peptide Arg-Gly-Asp-Ser (RGDS), and raising intraplatelet cAMP with Iloprost (a prostacyclin analogue). Aggregation required the interaction of the anti-SK Ab Fc domain with the platelet Fc-gamma receptor type II, also known as CD32, since: (i) it was blocked by the monoclonal antibody IV-3 directed against CD32, (ii) it did not occur with F(ab)'2 fragments, which block the response to the intact IgG. The clinical relevance of these platelet-activating anti-SK antibodies remains to be determined.(ABSTRACT TRUNCATED AT 250 WORDS)

Amino Acid Sequence↗

[Mid-term results of bioprosthesis in patients over 65 years].

Between 1979 and 1985, 79 patients over 65 years of age (mean 70.8; range 65-82 years) underwent valvular replacement with a bioprosthesis (aortic: 48, mitral: 26, aortic and mitral: 5). Of the 84 valves implanted, 56 were porcine and 28 were pericardial bioprostheses. The average follow-up was 66 months (total: 434 patient-years; range: 2 months-12 years). Twenty-three patients (29%) died; 13 of these deaths were related to the prosthesis and 10 were not formally related to the bioprosthesis. Of the latter 10 deaths, 7 were caused by malignant disease. Seven patients were reoperated for a complication due to the prosthesis (1.6% per patient-year): 5 primary tissue failure, 1 endocarditis, 1 perivalvular leak. Sixteen patients (20.3%) received oral anti-coagulants for atrial fibrillation; 6 of them (7.6%) had severe haemorrhagic complications (3 deaths). The actuarial survival was 76.2% at 5 years and 53.4% at 10 years. Actuarial survival without reoperation was 76% at 5 years and 42% at 10 years. Analysis of survival with respect to the type of bioprosthesis (porcine of pericardial), the valve orifice (mitral or aortic) and age (under or over 70 years) did not show any significant differences. Follow-up of patients over 65 years of age showed a high rate of haemorrhagic complications related to oral anticoagulant therapy for atrial fibrillation (6.8% per patient-year), a low rate of primary tissue failure (1.1% per patient-year) and a low reoperative mortality (1 death for 7 reoperations).

4-Hydroxycoumarins↗

[Third angioplasty, and after that?].

The authors studied retrospectively a series of 39 patients with a documented second restenosis after coronary angioplasty between January 1987 and November 1992, 33 of whom (31 men, 2 women) underwent a third procedure. The artery dilated was the left anterior descending (n = 17 including 9 proximal stenoses), the right coronary (n = 10), the left circumflex or its branches (n = 5) and the left main stem (n = 1). The lesions were confirmed to one vessel in 25 cases (75%) and affected two vessels in 8 cases (25%). The third angioplasty procedure was performed on a single artery in all cases. The average left ventricular ejection fraction was 60% (43%-75%). The diameter of the dilated artery was over 3.25 mm in 24% of cases (8/33). The primary success rate was 100% without any complications. The average period between the first and second angioplasties was 16 +/- 10 weeks, and between the second and third angioplasties 19 +/- 12 weeks. Angioplastic controls of the 3rd angioplasty were performed in 25 cases (75%). A third restenosis (n = 7) was treated by surgical bypass (n = 1), repeat angioplasty (n = 4), endocoronary stenting (n = 1) or medically (n = 1), with a global follow-up of 22 months (2-56 months), 2 patients underwent coronary bypass grafting, 2 have residual angina (contralateral lesion which could not be dilated), 1 had an infarct in the territory of an undilated artery, and 28 (85%) were asymptomatic. The restenosis rate after the third angioplasty procedure was 28% (7/25).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

[A rare course of spastic angina with normal coronary arteries].

The authors report the case of a 65-year-old woman smoker monitored for spastic angina. A first coronary arteriogram in 1986 failed to reveal any significant coronary lesion and was complicated by reversible occlusive spasm of the anterior interventricular artery. A second coronary arteriogram 6 years later because of recurrence of angina revealed the development of 70% stenosis of the coronary segment affected by the spasm. Such an outcome is rarely reported in the literature and raise the question of a possible link between spasm and the progression of atheroma.

Aged↗

Late results with bioprosthetic valves in the elderly.

AIM: We report the long-term outcome of aortic and mitral bioprostheses in patients over 65 years of age at the time of implantation. The aim was to determine actuarial patient survival, causes of death, and the rate of documented primary structural deterioration. METHODS: One hundred ten patients > or = 65 years of age (mean, 73.4; range, 65-82) underwent successful bioprosthetic valve replacement (aortic, n = 71; mitral, n = 32; both, n = 7) from 1979 to 1985. The valve was pericardial in 39 cases and porcine in 78. The mean follow-up was 8.5 years (101.9 months-total; 934 patient-years; range, 2 months to 15 years). RESULTS: Actuarial patient survival was 79.6% (71-86) at 5 years and 62.4% (52-71) at 10 years. Forty-four patients died, 21 from valve-related causes and 23 from other causes. Thirteen patients (11.8%) had reoperation for valve-related complications: 10 structural deteriorations, 2 paravalvular leaks, and 1 case of endocarditis. One surgical death occurred (7.7%). Twenty-six percent of the patients were receiving anticoagulants because of atrial fibrillation, and 6.4% developed severe bleeding (2.9% patient-years). CONCLUSIONS: Long-term follow-up of these patients > 65 years of age, undergoing bioprosthetic value replacement surgery revealed a low rate of documented primary structural deterioration (0.95% per patient-year), a low mortality rate on reoperation (7.7%), and a high mortality rate due to non-value-related causes (52.3%).

Aged↗

Thrombolysis and adjunctive therapies in acute myocardial infarction.

Thrombolysis and percutaneous transluminal angioplasty represent the cornerstone of the pharmacologic treatment of and the interventional approach to patients with myocardial infarction (MI). They are very effective. However, they are hampered by some critical limitations. Therefore, alternatives to standard thrombolytic therapy have been developed. Platelet glycoprotein (GP) IIb/IIIa blockade is under investigation and seems very attractive. This review will focus on the use of GP IIb/IIIa antagonists and thrombin inhibitors as adjunctive therapies to the thrombolytic treatment of patients with acute MI.

Acute Disease↗