[Prognostic evaluation with invasive technics in patients with hyperkinetic ventricular arrhythmias]. / Valutazione prognostica con metodiche invasive di pazienti con aritmie ipercinetiche ventricolari.

The prognostic value of induction of ventricular tachycardia (VT) by programmed electrical stimulation (PES) was analyzed in 123 patients: 64 (Group I) with spontaneous recurrent VT and 59 (Group II) without a history of serious arrhythmias. Thirty-three patients with spontaneous VT underwent coronary and left ventricular angiography to compare electrical instability with the presence of ventricular disfunction and/or the extent of coronary artery disease (CAD). PES reproducibly induced VT in 49/64 patients with spontaneous VT (sensitivity = 77%) and in 6/59 patients without VT (specificity = 90%). Twenty-two patients (66%) had ventricular disfunction defined by an ejection fraction of less than or equal to 40% or regional wall motion abnormalities. Only 4 patients (33%) had proximal 3-vessel CAD. The mean follow-up period was 16 +/- 12 months. Eight of Group I patients died suddenly and 24 had recurrent symptomatic VT. Three of Group I patients died (1 cardiac failure, 2 non-cardiac deaths), all the survivors were free of serious arrhythmias. In Group I patients mortality was correlated with: recent anterior myocardial infarction, inducible sustained VT with PES, ejection fraction less than or equal to 0.40, ventricular ipoasynergy and or at least one coronary stenosis greater than or equal to 70%. This study suggests that inducible VT is a marker of the risk of sudden death. Electrical instability may occur independent from the etiology of cardiopathy, ventricular disfunction and extent of CAD, but these parameters are correlated to global and sudden mortality in the group of patients with spontaneous VT.

[Disorders of formation and conduction of the cardiac impulse in hypertrophic and congestive primary myocardiopathy]. / Turbe della formazione e della conduzione dell'impulso nella miocardiopatia primitiva ipertrofica e congestizia.

Little information is available regarding cardiac automatism and conduction disturbances in patients affected by congestive (CCM) or hypertrophic (HCM) cardiomyopathies. For this reason 29 patients with HCM (10 cases) and CCM (19 cases) and disturbances of sinus node automaticity or AV conduction underwent an electrophysiologic study. Eight patients affected by HCM were also submitted to cardiac catheterization. Sinus node function was normal in each of the HCM patients, and impaired in 6 of the 19 CCM patients. The intra-atrial conduction was prolonged in only one CCM case. One HCM and 2 CCM patients showed an impaired intranodal AV conduction. Thirteen patients (44%) showed a prolonged HV interval (3 HCM and 10 CCM patients). No calcific deposits on the aortic valve were discovered by X ray stratigraphic examination in any of the patients. In 6 cases a progression of the conduction disturbances was observed. Ventricular pre-excitation was present in 4 patients (13%).

[Permanent endocardiac atrial pacing and sensing. Preliminary experience with screwing catheters]. / Sensing e pacing atriale endocardico permanente. Prima esperienza con cateteri a vite.

25 patients affected by sick syndrome (SSS) and normal AV conduction (15), SSS with AV conduction defects (6) and complete AV block (3) were treated respectively by means of atrial pacing. AV sequential pacing and atrial triggered-ventricular pacing. In the cases for atrial pacing and sensing, the Medtronic mod. 6957 screwing lead has been utilized. The technique resulted very simple and safe. The average atrial threshold was 1.4 +/- .05 V. (1.95 +/- 0.75 mA). The average total impendance was 740 +/- 240 ohm and the average atrial potential 2.7 +/- 1.43 mV. Two cases of early displacement of the lead were observed (due to the operator poor familiarity with the new lead). Temporary sensing defect was observed in two patients and promptly abolished by steroid therapy. No exit block was observed. The patients have been followed for an average period of six months. All the leads are sensing and pacing correctly.

[Old and new methods for control of pacemakers (author's transl)]. / Vecchie e nuove tecniche di controllo dei pacemaker.

First there is a description of present methods available for controlling the functioning of pacemakers, most of which are already being used in traditional clinic-electronic control. There follows a presentation of telephone monitoring (ECG + Pacing Rate) and its limits so far as photoanalysis is concerned. Mention is made of the new italian system of telephone monitoring which also includes measurement of amplitude and width of the pulse. Personal experience of the diagnostic value of photoanalysis is given. This concords with others as to its necessity to detect any failure from circuitry defects or from breakage or insulation of electrode. In conclusion the hope is expressed of actuating a completely trustworthy control system which includes a high degree of foreseeing failure (telephone monitoring) and diagnostic value (Rx + photoanalysis). At last the advantages of an automatic follow-up system in a pacemaker patient clinic are discussed.

[The experience in cardiac pacing at the Cardiology Department of St. Camillo Hospital (Rome) (author's transl)]. / L'esperienza della Divisione di Cardiologia dell'Ospedale San Camillo di Roma in tema di elettrostimolazione.

The experience of the Cardiac Electrostimulation Center of S. Camillo Hospital in Rome on 1503 patients treated with permanent pacemakers for an 11 year period is referred. The Authors analyze the increase of the activity of the Center during these years and some events that caused it. 94.5% of the patients were more than 50 years old; the dominant pathology has been ischemic and idiopathic cardiopathy, which together include 94.7% of the totality. The indication to the implant has been A-V block in 70% of the patients; intraventricular block in 20%; sick sinus syndrome in 10%. In the last years the prophylactic indication has increased (from 0.4% to 4.4%). 2459 pacemakers have been used, of which 79.5% was QRS-inhibit. The mercury prosthesis have been progressively substituted with the lithium ones. 1642 catheters (implant and reimplant) have been used; principally endocardic (95%) and monopolar (85%). The substitution of the catheter has been necessary in 9% of the totality; in 2.6% of the endocardic and in 15.9% of the epimyocardic. Among 50 electrodes, after a period of observation of about 7.7 years, 36 are still in function. The percentage of the complications has been 17.1%; the most important complications have been: dislocation (6%), microdislocation (1.5%), late high threshold (2.1%), failure of catheter (1.2%), generator malfunction (2.3%). The total mortality has been 15.4%; 0.2% caused by deficit of the implant; 2% sudden deaths and 13.2% not depending from the implant; 243 patients (16%) are not to be found. The frequency of out-patients controls has decreased in the last 2 years (from 3.8 controls per years to 1.8).

[The Italian experience in permanent pacing. A casuistry for more of 10 years: a policentric study (author's transl)]. / L'esperienza italiana con l'elettrostimolazione permanente a lungo termine. Casistica in trattamento da oltre 10 anni: studio policentrico.

According to a recent national survey, 387 patients were treated by permanent pacing in 10 Italian centers, between 1961 and 1966. Of these patients 205 have died; 131 (77 males and 54 females) are still alive and no informations could be obtained for the remaining 51 (13%). The overall survival of patients treated during this period of time is therefore not less than 34% which is comparable to that of general population of the same age group. The 131 patients still alive have totaled 1,486 years of pacing and have used up to 784 pacers. Comparing the incidence of the most common causes for replacement during the periods 1961-66 and 1973-77, electrode failures dropped from 21 to 0.9%; circuitry malfunctions occurred in 10.5 and 7.8%; battery depletion rose from 36.8 to 69% of the cases. According to their clinical conditions, the 131 patients on long-term follow-up can be grouped as follows: 62% are in class 1 or 2 of NYHA; 26.7% are in class 3, and 3.8% in class 4. Moreover, 53.4% of patients are living an active life, having some sort of occupation and 29% are holding a driving license.

[General anesthesia in patients with intraventricular conduction abnormalities (author's transl)]. / L'anestesia generale nei disturbi della conduzione intraventricolare.

This study was undertaken to assess the risk of developing complete heart block during general anesthesia in patients with bundle branch block. His bundle electrograms were recorded during sinus rhythm and after atrail pacing in 11 patients (5 LBBB, 2 RBBB, 3 RBBB and LAH, 1 RBBB and LBH) before and after administration of Pentothal 0.20 g e.v., Succinylcholine 1 mg/kg e.v., and breathing of fluothane 1%or Ethrane. Minimal effects on sinus functions and A-V node conduction was observed during anesthesia; Fluothane only increased slightly AH intervals (+11%). Both Fluothane and Ethrane effects on HV conduction was insignificant. In 9 patients HV intervals increased of 5% after Succinylcholine; 2 patients developed a complete heart block distal to his after the drug. Possible causes of the complete heart block are discussed and a direct effect of Succinylcholine is hypothesized.

[Modifications and control of the myocardial threshold with the Vario pacemaker EM 169 (author's transl)]. / Modificazioni e controllo della soglia miocardica con il Vario pacemaker EM 169

Measurements of threshold of electrical stimulation were performed in thirty patients with A-V block, at the time of implantation of the pacemaker, after 10 days, 1-2 months and 1 year. The Vario-pacemaker was used for the measurements. An increase in the stimulation threshold of about 260% was noted after 10 days and 1-2 months. One year after the implantation of the pacemaker, the myocardial threshold was about 200% of the initial value. The method is easy to perform. It is very useful to follow the myocardial threshold changes for a long period after the implantation.