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Biomedical subjects

R Frank

Publications and source records attributed to R Frank.

At least 559 records · Page 31Linked to original sources
PubMed1979

Surgical treatment for a complicated congenital aortic stenosis. The association of a three-level obstruction of the left ventricular outflow tract with mitral incompetence, coarctation of the aorta, and the Wolff-Parkinson-White syndrome.

We report a case of complex congenital aortic stenosis with obstruction at all three levels of the left ventricular outflow tract (subaortic, aortic, and supravalvular aortic stenoses) associated with a mitral malformation, coarctation of the aorta, and the Wolff-Parkinson-White syndrome. The subaortic stenosis was corrected by excision and myotomy, and the supravalvular stenosis by a widening prosthetic operation with a Dacron patch extending as far as the aortic ring, at which level a Björk-Shiley No. 17 aortic prosthesis was inserted. The mitral valve was replaced by a Lillehei-Kaster prosthesis. The coarctation of the aorta was not significant and was left alone. Permanent pacing was needed because of peroperative surgical section of the bundle of His. Reviews of the literature and the various techniques used to widen the left ventricular outflow tract are included.

Aortic Coarctation↗
PubMed1978

Encircling endocardial ventriculotomy: a new surgical treatment for life-threatening ventricular tachycardias resistant to medical treatment following myocardial infarction.

Ventricular tachycardias occurring after myocardial infarction (MI) and resistant to medical treatment were successfully treated in 5 patients by encircling endocardial ventriculotomy. All patients had a history of MI. The delay between MI and ventricular tachycardias ranged from 1 month to 8 years. A reentrant mechanism was demonstrated by laboratory studies. Under cardiopulmonary bypass, the left ventricle was entered through the thin fribrous scar. Encircling endocardial ventriculotomy was carried out from the inside of the ventricle, through the whole thickness of the normal myocardium, and along the border of the endocardial fibrosis, which delineated the area of diseased myocardium. The ventriculotomy was placed in the free wall or in the septum or in both of these locations. It was repaired and the left ventricle was closed. Drug therapy was discontinued after operation. No ventricular tachycardias recurred during a follow-up period of 6 to 24 months. The effectiveness of encircling endocardial ventriculotomy is explained by the exclusion of the entire diseased area, especially the border zone and the septum. This technique is useful in any location of MI.

Cardiopulmonary Bypass↗
PubMed1978

Risks of delayed potentials in pacemaker patients prone to ventricular tachycardia.

Late potentials occurring after completion of the QRS complex have been observed in patients prone to ventricular tachycardia. They were recorded either during epicardial studies or in the catheterization laboratory. This paper describes such abnormal myocardial activity and discusses their potential effects on cardiac pacemakers.

Electrocardiography↗
PubMed1978

[Electrocardiography of delayed potentials in post-excitation syndrome].

Electrophysiological investigation and pericardial mapping have succeeded in isolating a particular type of ventricular tachycardia occurring in young subjects with no coronary artery disease who have dysplasia of the right ventricle. When these patients are no longer controlled by medical treatment, they may benefit from surgery. This condition is characterised by the presence of delayed potentials which appear after the end of ventricular depolarisation as recorded by épicardial mapping. This post-excitation phenomenom may also be demonstrated either by an intracavitary electrode or sometimes on an amplified ECG. This study describes a new method using the techniques of signal averaging and summation technique to demonstrate the delayed potential in the post-excitation syndrome. It is non-invasive, and seems to give better results than those obtained from intracavitary exploration.

Adult↗
PubMed1978

Residues of organochlorine insecticides and polychlorinated biphenyls in fish from Lakes Huron and Superior, Canada--1968-76.

Five species of fish from Lake Superior and 12 species from Lake Huron were analyzed for organochlorine pesticides and polychlorinated biphenyls (PCBs) between 1968 and 1975. Mean residues of sigma DDT peaked at 1.72 ppm and 7.60 ppm in lake trout (Salvelinus namaycush) from Lakes Superior and Huron, respectively. By 1975, the mean level of sigma DDT had decreased in lake trout and was highest in bloaters (Coregonus hoi) from both lakes: 1.06 ppm and 1.87 ppm, respectively. Dieldrin levels in fish from Lake Superior changed little over the same period. However, in 1969-70, dieldrin levels in fish from Lake Huron exceeded the 0.3 ppm tolerance level set by Health and Welfare Canada or the Food and Drug Administration, U.S. Department of Health, Education, and Welfare in 5 percent of lake whitefish (Coregonus clupeaformis) and 10 percent of bloaters. By 1975, 50 percent of bloaters caught in Georgian Bay and North Channel had dieldrin levels above 0.3 ppm. PCB residues declined in lake trout and lake whitefish caught in Lake Superior between 1971 and 1975, but increased slightly in bloaters and white sucker (Catostomus commersoni). Mean PCB residues in bloaters caught in Lake Huron in 1969-71 and 1975-76, and splake (Salvelinus fontinalis and S. namaycush) and cisco (Coregonus artedii) caught in 1975 exceeded the 2 ppm tolerance level.

Animals↗
PubMed1978

Residues of organochlorine insecticides and polychlorinated biphenyls in fish from Lakes Saint Clair and Erie, Canada--1968-76.

Eighteen species of fish from Lake Saint Clair and 19 species from Lake Erie were analyzed for organochlorine pesticides and polychlorinated biphenyls (PCBs) between 1968 and 1976. Mean residues of sigma DDT peaked at 1.19 ppm in longnose gar (Lepisosteus osseus) caught in Lake Saint Clair in 1970-71, but had declined in all species by 1975-76. Dieldrin levels in fish tissues increased over the same period. White bass (Morone chrysops), caught in 1975 in Lake Erie, had the highest mean residue of dieldrin at 0.17 ppm. PCB residues increased in some species and decreased in others. PCB residues exceeding the tolerance level of Health and Welfare Canada were found in the following: from Lake Saint Clair, smallmouth bass (Micropterus dolomieui) in 1975 and channel catfish (Ictalurus punctatus) in 1971; from Lake Erie, coho salmon (Oncorhynchus kisutch) in 1970, smallmouth bass, alewife (Alosa pseudoharengus), freshwater drum (Aplodinotus grunniens), and gizzard shad (Dorosoma cepedianum) in 1971, and white bass in 1971 and 1976.

Animals↗
PubMed1978

[Recurrent ventricular tachycardia and parchment right ventricle in the adult. Anatomical and clinical report of 2 cases].

Two patients, aged 52 and 55 years, were admitted to hospital for attacks of recurrent ventricular tachycardia for which preventive treatment was difficult. The crises were of one type, with left-sided delay. The findings on clinical examination, electrocardiography, haemodynamic and arteriographic investigation and at post-mortem were those of the parchment right ventricle syndrome of the adult. Electrophysiological investigation in the 2 cases indicated that a re-entry mechanism underlay the attacks of tachycardia. Late activation of the pulmonary infundibulum was responsible for a post-excitation potential on the surface and intra-cavitary leads. Mapping carried out during ventricular tachycardia in one case demonstrated the pathway for re-entry at the level of the pulmonary infundibulum.

Electrophysiology↗
PubMed1978

Modern concepts of ventricular tachycardia. The value of electrocardiological investigations and delayed potentials in ventricular tachycardia of ischemic and nonischemic etiology (31 operated cases).

Concepts on ventricular tachycardia (VT) have markedly changed in the last 10 yr, with the help of sophisticated electrophysiological methods of study. The importance of the reentry phenomenon in the mechanism of the arrhythmias has been pointed out by stimulation procedures. Epicardial mapping allowed the localization of the abnormal zone where delayed impulses could allow reentry. Surgical techniques have been developed from these observations, to prevent reentrant VT in some refractory cases.

Action Potentials↗
PubMed1977

[Current indications of coronary arteriography in coronary artery disease (with the exception of acute myocardial infarction) (author's transl)].

The indications of coronary arteriography have multiplied in recent years. Therapeutic indications have followed knowledge of the good results of revascularisation surgery. Initially limited to severe stable angina improved little or not at all by major anti-angina agents, they have been extended, in the view of many, to include various types of unstable angina where, in addition to the symptomatic improvement obtained, an attempt is made to decrease the incidence of myocardial infarction and of long term mortality. Indications relative to determination of the extent of disease may be preventive: the fear of severe coronary lesions on the basis of effort test results, the fear of a second infarction immediately following a primary lesion, or as a virtually routine examination in young individuals in order to better assess the degree of disease and to guide treatment. Diagnostic indication should be rare.

Angina Pectoris, Variant↗
PubMed1977

Glyoxalase I polymorphism in South African Bantu-speaking negroids.

The newly described genetic polymorphism of glyoxalase I (GLO) is studied in seven ethnically defined Negroid samples from South Africa (total: n = 843). The allele frequencies between the different Negroid samples studied vary only marginally. However, the allele frequency of GLO1 for the South African Negroid samples combined (i.e., p = 0.259), is highly significantly lower than that for Caucasoid samples.

Alleles↗
PubMed1977

Ammonia in the human airways: neutralization of inspired acid sulfate aerosols.

In the human being, expired ammonia concentrations from 7 to 520 micrograms per cubic meter are controlled by the last airway segment traversed by the air, and such concentrations are higher in the mouth than nose. Inspired submicrometric sulfuric acid aerosol at a mass concentration of 600 +/- 100 micrograms per cubic meter was found to be an ammonium salt with an average ammonium to sulfate molar ratio of greater than or equal to 1, when sampled within 0.5 second after exhalation.

Aerosols↗
PubMed1977

Haplotype analysis of the linkage group HLA-A:HAL-B:Bf and its bearing on the interpretation of the linkage disequilibrium.

The analysis of 650 HLA-A:HAL-B:Bf three-factor haplotypes revealed significant associations only between alleles of the very closely linked genes HLA-A and HLA-B, and Bf, respectively. Most striking is the highly significnat association of the rare Bf variant F1 with HLA-B18 and of S1 with HLA-B13, HLA-B14, and HLA-Bw21. Only random allele distributions were observed when considering the somewhat more distant genes HLA-A and Bf or the higher order interaction at all three genes. From these findings it seems likely that the linkage disequilibrium within the MHC is not due to selective forces, but rather due to a short evolutionary period.

Chromosomes, Human, 6-12 and X↗