The use of light reflection rheography in diagnosing venous disease and arterial microcirculation.

The use of light reflection rheography (LRR) has reached an important level in the past few years. Using the originally construed and conceived RRL 001 device, we present the basic principles, the working technique and the limits of this method. We will use two magnetic amplifiers, one for the finger tip, which measures the capillary blood flow at this level and a venous magnetic amplifier which measures the blood flow in the venous plexuses at a 1-2 mm depth. The detection of the blood flow in the subcutaneous (hypodermic) venous areas leads to the diagnosis of profound thrombophlebitis and venous valves insufficiency. The detection of the capillary flow in the finger tip, its presentation as a curve, measuring the pressure of the inter digital arteries (using Riva Rocci method), establishing the index of systolic pressure make possible the understanding of the gravity of the existing hemodynamic disorders (especially in what concerns the Raynaud syndromes), the supervision of the original disease and the efficiency of the treatment. Weindorf was the first one to use the RRL technique in medicine in 1985 and, after 1997, it has been developed through Sproule's work. Within The Medical Clinic of the Municipal Hospital, a light reflection rheograph has been built and forwarded as innovation. The device has been used for 2 years in the diagnosis of venous disorders and peripheral microcirculation disorders. In this article we present the principles of the LRR examination of the lower limb venous system and of the microcirculation of the fingers of the upper limbs, an examination based upon our own experience which includes 72 examinations.

The efficacy of sublingual verapamil in controlling rapid ventricular rate in chronic atrial fibrillation.

The efficacy of sublingual verapamil (Verapabene, 40 mg) in acute control of high ventricular rate was assessed in 20 patients with chronic atrial fibrillation (AF) of ischemic origin (class NYHA II and III). The effect on irregularity of the rhythm was also studied using time domain parameters of heart rate variability. Four ECG recordings (before, and at 10, 30 and 60 minutes after the administration), of 10 minutes each, were performed in every patient in basal conditions. The parameters were compared using paired t-test and Wilcoxon's test. Mean heart rate became significantly lower (p = 0.0064) after 10 minutes, and reached progressively the lowest value after 60 minutes (from the initial 112.9 beats/min to 90.6 beats/min, after 60 minutes, p < 0.0001). The irregularity parameters (SDNN--from 114.7 ms to 148.6 ms, rMSSD--from 152 ms to 205.9 ms) and the NNmin interval (from 353 ms to 404.5 ms) increased significantly after 30 and 60 minutes (p < 0.0001), but the frequency corrected irregularity (coefficient of variability) remained unchanged (p > 0.4). Sublingually administered verapamil proved to be an efficient alternative in acute control of rapid ventricular rate in AF. The method has the advantage to be applicable by a properly instructed patient itself.

The monophasic action potential: a simple in vivo model to evaluate the effects of antiarrhythmic drugs at atrial level.

Monophasic action potential (MAP) represents an extracellular recording of electrical potentials variations produced simultaneously by several cells. Even if it does not represent the real cellular action potential, monophasic action potential generally reproduces with accuracy that aspect, being useful especially in the assessment of myocardial repolarisation phases. Monophasic action potential recording was performed with a quadripolar catheter designed by Franz; the quality of recordings was good and the procedure is safe. In clinical electrophysiology, monophasic action potential may be helpful in the study of certain aspects that cannot be evaluated adequately by standard electrophysiological techniques. The study was performed on six patients, in drug-free state. The duration of monophasic action potential at 90% of repolarisation and the atrial effective refractory period, at three basic cycle lengths (600, 500 and 400 msec) were determined. Both monophasic action potential duration at 90% of repolarisation and the atrial effective refractory period shortening at short cycle length and a linear correlation between these two parameters were seen. We conclude that the correlation between monophasic action potential duration and the effective atrial refractory period may be a simple and useful model to characterise in vivo the electrophysiologic profile of antiarrhythmic drugs.

Treatment of atrial flutter and rapid atrial tachycardia with endocavitary atrial pacing.

Fourteen patients with atrial flutter (AFL) and rapid atrial tachycardia (AT) (8 AFL type I, 2 AFL type II and 4 AT) were treated with endocavitary atrial pacing (EAP). In 10 patients no antiarrhythmic agent was during this study and in 4 patients digoxin and/or verapamil was administered before. Conversion to sinus rhythm was successfully achieved in 7 patients, 50% (4 AFL type I and 3 AT). Primary success rate (return to sinus rhythm either immediately or after < 10 min of atrial fibrillation) was 71% (5/7) (2 AFL type I and 3 AT); delayed success (conversion to sinus rhythm in > 10 min, but < 24 h) was observed in 2 cases (29%) with AFL type I. At five patients AFL was converted in stable atrial fibrillation (4 AFL type I and 1 AFL type II). EAP failed to terminate the arrhythmia in 1 patient with uncommon AFL (type II) and 1 case with AT. EAP included single extrastimuli, coaction, single decremental atrial extrastimuli and incremental atrial pacing (burst) during AFL or AT. In conclusion, EAP is a method with few complications and has efficacy for converting AFL and rapid AT sinus rhythm or to atrial fibrillation.

Electrophysiologic evaluation of extrinsic and intrinsic sinus node dysfunction.

Electrophysiologic investigation was done for ten patients with clinical and ECG criteria for sick sinus syndrome (SSS). Sinus node function was assessed through corrected sinus node recovery time (CSNRT) and sinoatrial conduction time (SACT), before and after autonomic blockade (AB) with propranolol 0.2 mg/kg and atropine 0.04 mg/kg, given intravenously. Four patients having electrophysiologic parameter in normal range before AB were not considered as SSS. In three patients extrinsic sinus node dysfunction (SND) was found, the pathologic values of CSNRT and SACT being normal after AB, and in one patient with sinus bradycardia, the sinus node function was difficult to be appreciated. In two patients only intrinsic SND was found and, in consequence, pacemaker device was implanted.

Computerized system for assessing heart rate variability.

The principal theoretical, methodological and clinical aspects of heart rate variability (HRV) analysis are reviewed. This method has been developed over the last 10 years as a useful noninvasive method of measuring the activity of the autonomic nervous system. The main components and the functioning of the computerized rhythm-analyzer system developed by our team are presented. The system is able to perform short-term (maximum 20 minutes) time domain HRV analysis and statistical analysis of the ventricular rate in any rhythm, particularly in atrial fibrillation. The performances of our system are demonstrated by using the graphics (RR histograms, delta RR histograms, RR scattergrams) and the statistical parameters resulted from the processing of three ECG recordings. These recordings are obtained from a normal subject, from a patient with advanced heart failure, and from a patient with atrial fibrillation.

Role of ketanserin in the treatment of the essential arterial hypertension associated with ischemic heart disease.

This clinical study was set-up to evaluate the antihypertensive effect of ketanserin in essential hypertension (EH) associated with asymptomatic ischemic heart disease (IHD) in twenty-seven patients. Every patient received 20-40 mg ketanserin, a selective S2 serotoninergic antagonist, twice daily, for a three-month period. The blood pressure (BP) was significantly lowered during the treatment with ketanserin, much more in female patients and elderly group.

Postextrasystolic changes in ventricular depolarization (electrocardiographic observations).

Postextrasystolic changes in ventricular depolarization were found in patients with coronary artery disease in two situations: a) after a compensatory postextrasystolic pause and, b) after an interpolated ventricular beat. The explanation and the underlying conditions of this phenomenon are discussed. In our opinion the postextrasystolic change may be a silent myocardial ischemia.

Postextrasystolic ischemic T wave. A possible silent ischemia.

Postextrasystolic potentiation may produce in some situations a negative T wave. This situation is presented in two cases, and it is assumed that this phenomenon may be considered as silent myocardial ischemia.

Hypothesis of transition in two ways from atrial fibrillation to sinus rhythm.

A hypothesis of transition from atrial fibrillation to sinus rhythm in close relation with monophasic action potential duration is proposed. The first way: the prolongation of the right atrial refractoriness reduces the wave fronts below a critical number and their collision terminates the arrhythmia. The second way: progressive shortening of refractoriness at a critical level with block and collision of wave fronts.

Peculiar atrial fibrillation in patients working with electric current.

During a period of 20 years, 8 patients with atrial fibrillation, without other cardiac abnormalities, resistant to electroconversion, but successfully defibrillated with quinidine, were examined. All were males, aged 40 to 50 years, working with electric current and exposed for many years to frequent electric shocks. The authors consider that chronic exposure to electric current induces a special form of atrial fibrillation, resistant to electric conversion. The inefficiency of the electroshock therapy in such cases might be explained by the increase of transthoracic impedance consecutive to repeated electrocutions.

Intracardiac electrical discharge in terminating atrial fibrillation.

A new intracavitary technique for internal defibrillation in atrial fibrillation is presented. The discharge takes place between the distal electrodes of the catheter placed in the right atrium and a thoracic paddle. Four cases are discussed, and the indications for this type of defibrillation are considered. Internal defibrillation can be done when, for other purposes, an electrode catheter is already placed in the right atrium.

Preatrial activity recorded by intracavitary and transthoracic techniques.

Two methods to record preatrial activity, that is, sinus node potential are presented. One, during right atrial catheterization through an electrode catheter, and the other, using transthoracic recordings with a high amplification and derivation of the electric signals. The sinus node potential duration represents the sino-atrial conduction time (SACT), a useful parameter for the sinus node function evaluation.

Digitalis, a defibrillatory drug.

Digitalis glycosides have an antiarrhythmic effect in atrial fibrillation, as defibrillatory drugs. These drugs could be classified in a group of antiarrhythmic drugs close to the ventricular defibrillating drugs recently proposed. The reasons for this opinion are shown in this work.

The residual myocardial contractile reserve in the rational use of digitalis.

A simple noninvasive method for the estimation of residual myocardial contractile reserve by using the postextrasystolic stimulation and systolic time intervals is proposed. The rational use of digitalis, avoiding the toxic effects, is possible only if the presence or absence of the residual contractile reserve is taken into consideration.

Chest-wall and transesophageal stimulation in the functional evaluation of patients with permanent pacemakers.

For the functional estimation of artificial pacemakers, we have used two techniques: chest-wall stimulation and transesophageal stimulation. Transesophageal stimulation was always effective in inhibiting the generator, and it was used when chest-wall stimulation was ineffective. These two tests can be easily performed and are of remarkable usefulness in the follow-up of patients with permanent pacemaker.

A simple bedside technique in the study of the WPW syndrome.

A simple method for the study of the WPW syndrome, which can be performed at the patient's bedside, is presented. Using standard ECG, vagal maneouvers, ajmaline test, precordial mapping, vectorcardiography, electrode catheters positioned in the right atrium and esophageal catheters, the site of accessory pathways, and the complex arrhythmias occurring in these patients can be understood and medically treated.