Biomedical subjects

A Medvedowsky

Publications and source records attributed to A Medvedowsky.

6 recordsLinked to original sources

PubMed1992

[Electric stimulation of the spinal cord in arterial diseases of the legs. A multicenter study of 244 patients].

From January 1985 through January 1990, 244 patients (168 males, 76 females, mean age: 69 +/- 14 years) received epidural spinal cord stimulation for the treatment of advanced, nonreconstructable, peripheral vascular disease of the lower limbs due to atherosclerosis in 180 patients, atherosclerosis and/or diabetes in 49, and thromboangiitis obliterans in 15 patients: previous surgery included 101 bypass-grafts in 70 patients, 51% of which below the knee, and 117 sympathectomies in 113 patients as the last resource in face of distal peripheral vascular disease of the lower limbs. Mean ankle-to brachial systolic pressure ratio was .31 +/- .34 on symptomatic limbs; due to pain and advanced disease, walking capacity was assessed in only 151 patients, either on treadmill in 25, or in a metered corridor in 126; angiogram of the lower limbs was performed in every patient unless one not older than three months was readily available; pain at rest was assessed after an analogical scale; partial transcutaneous oxygen tension was measured on the dorsum of the fore-foot of 77 symptomatic limbs (mean: 13.35 +/- 14 mmHg). According to clinical and functional evaluation, 18 patients had exertional ischemia (group I), 87 had permanent ischemia with pain at rest and no tissue loss (group II), and 139 had chronic tissue loss (group III), including 93 ischemic ulcers (mean surface: 3.7 cm2, mean duration: 3.5 months) in 88 patients, 27 limited gangrene, and 24 previous limited non-healing distal amputation. After temporary spinal cord stimulation at T12-L1 level (mean duration: 9 +/- 4 days) with a percutaneous quadripolar electrode lead had allowed for selection of responders, 212 patients received an implantable neurostimulator.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗

PubMed1982

Part of the autonomous nervous system in the development of chaotic post-extrasystolic pictures. Electrophysiological and pharmacological studies of 49 cases.

The interpretation of post-extrasystolic parameters and their significance is discussed. Programmed extrastimulation according to Strauss was carried out in 49 cases, before and after atropine and propranolol administration. The result was a computable sinoauricular conduction time (SACT), a chaotic picture, or an ascending line without plateau. The patients were selected on basis of their intrinsic heart rates (IHR). If the total SACT exceeded 250 ms, the chaotic post-extrasystolic picture and the ascending 1st phase without plateau were considered pathologic, then after drug testing the ratio of pathologic parameters decreased from 54 to 22% in cases with normal IHR. Including cases with pathologic IHR the ratio increased from 55 to 90%, especially in asynchronous chaotic pictures. After drug testing the chaotic forms were always replaced by a plateau in cases with normal IHR, but in pathologic ones the chaotic picture appeared to be a dominant electrophysiological parameter. It follows that the autonomous nervous system has its part in the development of chaotic post-extrasystolic pictures. A plateau in the post-extrasystolic curve could mean a functional organization and synchronism rather than a conduction disturbance; to the latter a high-level plateau would correspond.

Atropine↗

PubMed1982

Synchronized and desynchronized sinus node activity.

In certain cases because of sinus arrhythmia and/or anarchic return and postreturn cycles caused by premature atrial stimulation, the sinoatrial conduction time cannot be calculated since a chaotic postextrasystolic pattern appears. We examined 49 patients with a history and ECG signs suggesting sinus node dysfunction by programmed extrastimulation method as proposed by Strauss et al. prior to and after pharmacologic autonomic blockade (with propranolol 0.2 mg/kg body weight and atropine sulfate 0.04 mg/kg intravenously). Patients with normal intrinsic heart rate (IHR) (n = 31) showed chaotic postextrasystolic responses in 38%, which in every case could be eliminated by autonomic blockade, resulting in a clear I and II phase with a well estimated intrinsic conduction time. Patients with pathologic IHR (n = 18) gave chaotic responses in 22% which after drug testing increased up to 72%. The chaotic postextrasystolic patterns are to be interpreted as the desynchronization of the sinus potentials, while plateau (phase II) as functional integrity, synchronized activity of the sinus node, dependent on the momentaneous balance of the autonomous tone, and on the integrity of the pacemaker cells. The desynchronized chaotic responses are considered on one hand as a dystonic neurovegetative electrophysiologic characteristic, on the other hand as a primary extrastimulation parameter of the intrinsic sinus node dysfunction.

Adult↗

PubMed1982

Electrophysiological classification of normal and pathological sinus node function.

The sympathetic and parasympathetic neurological cardiac effects were blocked with atropine and propranolol. The intrinsic heart rate (IHR) was determined and rapid atrial pacing (RAP) was carried out before and after administration of the drugs. The primary and secondary postpacing parameters were examined in both circumstances. Normal (n = 31) and pathological (n = 20) cases were differentiated on the basis of the IHR. In the secondary phase (PPC 2-10) after autonomic blockade returned to the basic frequency was of exponential character in the great majority of normal IHR cases. Anomalies may appear in both the primary and secondary phases. They are of different types: one of them concerns the recovery time; another electrophysiological anomaly occurs when there is no return to the predrive normal cycle length after pharmacological neurotomy. In the secondary phase there may appear sinoauricular blocks. They may depend on or appear independently of the effect of the vegetative nervous system. The new test allows a physiopathological classification of normal and pathological sinus node function.

Adult↗

PubMed1980

[Sinus node dysfunction. Clinical outcome and results of cardiac pacing].

112 patients (average age 66 +/- 13 years) with sinus node dysfunction, selected on clinical, electrocardiographic and electrophysiological criteria, were followed up for a period of 3 to 55 months (average: 30,2 months). Permanent cardiac pacing was instituted in 59 patients (52,6 p. 100), and the remaining patients treated medically. 25 patients were lost to follow up (22,3 p. 100: 5 paced, 20 non paced). 16 patients died (14,2 p. 100): mortality was relatively early (average 11,7 months) and higher in patients with pacemakers (15/16); the causes of death were acute heart failure (8 cases), and cerebral vascular accident (3 cases). In the surviving paced patients neurological symptoms completely regressed. In this series, the life expectancy of patients with sinus node dysfunction seemed to depend mainly on the state of their myocardium, but the functional prognosis was clearly improved by cardiac pacing.

Adolescent↗

PubMedDate not supplied

[The value of heparin in postphlebitic syndromes].

Post-phlebitic syndromes, the result of late diagnosis at the acute stage and/or inappropriate treatment, are disorders which are still very widespread, chronic, and more or less incapacitating. For fifty years, there has been no new really and lastingly active medication to improve the local condition and check the aggravation. However, heparin is still the least ineffectual form of medication. Applied in series of treatment of 10/15 days, preferably by route IV, it alone is able to produce consistently fair results. Taken on average with the application precautions, the risks with standard doses are practically nil.

Chronic Disease↗