Slow ventricular tachycardia in a 91-year-old man with implantable cardioverter-defibrillator and acute respiratory failure.

Slow ventricular tachycardia (VT) in patients with devices such as an implantable cardioverter - defibrillator (ICD) is more common than in the rest of the population. The incidence in elderly patients with an ICD remains largely unknown. In younger patients, slow VT is generally asymptomatic or associated with limited clinical relevance. It may be efficiently and safely terminated by anti-tachycardia pacing. We present a case of slow VT in a 91-year-old man with ICD with type 1 acute respiratory failure and drowsiness. Very elderly patients who have poor cardiac reserve and minor deterioration in cardiac function can face serious consequences such as ventricular fibrillation, cardiac arrest, and sudden cardiac death. The persistent ventricular rhythm may have a deleterious effect on their haemodynamic status, with potential aggravation of symptoms of heart failure and further impairment of ventricular function.

Tako-tsubo cardiomyopathy complicated by recurrent torsade de pointes in a patient with anorexia nervosa.

We report the case of a 57-year-old woman with anorexia nervosa showing evidence of "tako-tsubo" cardiomyopathy complicated by several syncopes due to recurrent episodes of torsades de pointes. Prolongation of QT interval and QT dispersion have been reported both in the "tako-tsubo" cardiomyopathy and in anorexia nervosa. The QT prolongation and the QT dispersion has been linked as risk indicators for sudden cardiac death. The combination of "tako-tsubo" cardiomyopathy with a condition associated with the prolongation of QT and/or with an increase of QT dispersion, such as anorexia nervosa, makes the acute and subacute prognosis of this disease much more severe than usual.

Osborn waves in severe accidental hypothermia secondary to prolonged immobilization and malnutrition.

We report the case of a 77-year-old man, in whom accidental hypothermia was secondary to prolonged immobilization and malnutrition. The electrocardiogram showed typical Osborn waves, which disappeared with the rewarming of the patient. The diagnosis of hypothermia is easy in patients with a history of prolonged exposure to a cold environment but accidental hypothermia may also occur as a consequence of prolonged immobilization and malnutrition. ECG analysis is very important for a correct and fast diagnosis.

Tako-tsubo cardiomyopathy in a patient with pacemaker syndrome.

We report the case of a 71-year-old woman, with a dual chamber pacemaker (PM), in whom a PM syndrome, due to loss of atrial sensing and pacing, was associated with a tako-tsubo cardiomyopathy (TTC). The repositioning of the atrial lead immediately improved symptoms, whereas complete regression of left ventricular wall motion abnormalities occurred after 1 month. We hypothesize that haemodynamic and hormonal responses associated with a PM syndrome, such as increased levels of catecholamines, may account for TTC in our patient.

[Competitive pacing in a patient with DDD pacemaker and bigeminal ventricular extrasystoles]. / Stimolazione competitiva in un portatore di pacemaker DDD con extrasistoli ventricolari bigemine.

The ECG recorded from a patient with DDD pacemaker showed variable responses of the pacing system to bigeminal ventricular extrasystoles, dependent on the coupling interval of premature beats. For relatively short coupling intervals, the premature spontaneous event was detected by the pacemaker, inhibiting both atrial and ventricular output, and resulting in a relatively long pacing pause. In slightly less premature end-diastolic extrasystoles, in contrast, the pacing system delivered an atrial spike that was superimposed upon the spontaneous premature QRS complex (pseudo-pseudofusion); under these circumstances, the atrial spike was followed, at the end of the programmed atrioventricular interval, by a ventricular spike falling on the extrasystolic T wave apex (competitive ventricular pacing). This phenomenon, however, did not express a sensing malfunction, but was due to post-atrial ventricular blanking (PAVB), a short period initiated by the atrial spike during which ventricular sensing is temporarily disabled, so that no signal can be detected. Finally, whenever premature end-diastolic impulses occurred after PAVB, during the brief interval defined ventricular safety pacing, the spontaneous event was sensed, being followed by an earlier-than-expected ventricular spike, whose prematurity was aimed at avoiding the occurrence of an artificial impulse upon the T wave of extrasystole. In conclusion, despite several not sensed ventricular extrasystoles and competitive pacing, no sensing malfunction was present. This case demonstrates how complex can be the electrocardiographic analysis of a DDD pacemaker, owing to the many complicating phenomena related to this pacing mechanism.