1/212. Predominant tricuspid stenosis secondary to bacterial endocarditis in a patient with permanent pacemaker and balloon dilatation of the stenosis. In a 49-year-old woman with sick sinus syndrome and a permanent VVI pacemaker, severe tricuspid stenosis and its clinical consequences developed 4 years after the attack of endocarditis. Besides the quite unusual occurrence of lead related tricuspid stenosis, successful treatment with balloon dilatation is the unique feature of this case. ( info) |
2/212. Possible involvement of hypothyroidism as a cause of lithium-induced sinus node dysfunction. Although several reports have stated that even therapeutic levels of lithium can induce sinus node dysfunction, the mechanism has not been fully elucidated. We present here two patients with sinus node dysfunction after long-term lithium therapy. Following lithium discontinuation, sinus node function recovered completely. After resuming lithium, however, irreversible sinus node dysfunction recurred and a permanent pacemaker was implanted in one patient. The serum concentration of lithium was within therapeutic levels. Nevertheless, hypothyroidism was associated with the sinus node dysfunction in both patients. Thus, thyroid function may play an important role in sinus node dysfunction induced by lithium. ( info) |
3/212. lead failure due to the subclavian crush syndrome in a patient implanted with both standard and thin bipolar spiral wound leads. Subclavian crush syndrome is a well-described cause of pacemaker lead failure resulting from an entrapment of a lead or leads between the clavicle and the first rib. A new thinner lead (ThinLine) was designed to minimize this complication. Our patient developed atrial and ventricular lead subclavian crush syndrome with both conventional and thin leads. ( info) |
4/212. Familial isolated noncompaction of the left ventricular myocardium. Noncompaction of the ventricular myocardium (sometimes referred to as 'spongy myocardium') is believed to represent an arrest in endomyocardial morphogenesis. The gross anatomical appearance is characterized by numerous excessively prominent trabeculations and deep intertrabecular recesses. Distinct morphological features can be diagnosed on two-dimensional echocardiography. We present here a family of isolated noncompaction of the left ventricular myocardium, in which 5 affected individuals suggested the presence of some genetic abnormalities in this disorder. ( info) |
5/212. Dynamic left ventricular arterial pressure gradient and sick sinus syndrome with heterozygous Fabry's disease improved following implantation of a dual chamber pacemaker. A 63-year-old woman with heterozygous Fabry's disease, sick sinus syndrome, sinus pauses, congestive heart failure, syncope, and a dynamic pressure gradient between the left ventricle and systemic arteries underwent implantation of a dual chamber (DDD) pacemaker. Following pacemaker implantation, the pressure gradient has been reduced and congestive heart failure controlled for the past 3 years. ( info) |
6/212. exercise-induced uncommon atrioventricular nodal reentrant tachycardia with sick sinus syndrome: a case report. exercise seldom provokes tachycardia in patients with paroxysmal supraventricular tachycardia (PSVT). This report presents a case of exercise-induced uncommon atrioventricular nodal reentrant tachycardia (AVNRT) with sick sinus syndrome. Treadmill exercise testing provoked AVNRT of long RP' with good reproducibility. Uncommon AVNRT was confirmed by the lack of atrial pre-excitation during PSVT and para-Hisian pacing. The patient has been successfully treated with verapamil and DDD pacing for 5 years. ( info) |
7/212. Intermittent sinus bigeminy as an expression of sinus parasystole: a case report. A case of sinus parasystole is reported. The diagnosis of sinus parasystole is relatively difficult because there is no difference between the basic sinus P wave and the parasystolic wave. Sinus parasystole is diagnosed according to the following electrocardiographic criteria: (1) premature P waves having contour identical to P waves of basic beats; (2) intervals between premature P waves mathematically related. In the case reported, the coupling intervals during long phases of intermittent sinus bigeminy were nearly fixed, because there was little variability in the returning cycles, making the diagnosis of sinus parasystole difficult. ( info) |
8/212. Interelectrode (Accufix) lead fracture. An interelectrode fracture was diagnosed 7 years after the implantation of an Accufix lead. The lead body separated from the tip with the helix screwed into the atrial wall. The retention wire was intact and may have contributed to the lead rupture. ( info) |
9/212. Unexpected loss of bipolar pacing with implanted dual chamber pacemakers. Bipolar leads are most commonly used in the current practice of pacemaker therapy. In our study of 124 patients implanted with Guidant/Cardiac Pacemakers (CPI) Vigor dual chamber pacemakers, 5 patients had unexpectedly abrupt increases in bipolar lead impedance and pacing threshold 2 weeks to 18 months postimplantation without changes in sensing function. With the lead configuration reprogrammed to unipolar, the lead impedance and pacing threshold were restored to appropriate ranges. The changes in bipolar lead parameters can be caused by the CPI's "Quick Connect" (QC1) header lead system incorporated in these pacemakers. ( info) |
10/212. Successful treatment of severe orthostatic hypotension with cardiac tachypacing in dual chamber pacemakers. Orthostatic hypotension is an evolving and disabling disease usually observed in elderly patients with dramatic consequences on morbidity, mortality, and impairing the quality of life. We studied the effects of the pacing rate and AV interval on the blood pressure drop in the upright position in two patients with previously implanted pacemakers for sinus node dysfunction. Although the AV interval did not affect the blood pressure drop in the upright position, tachypacing at 100 paces/min improved it dramatically and prevented syncope. Cardiac tachypacing is a useful therapeutic option in severe refractory orthostatic hypotensive patients, especially those with chronotropic incompetence. ( info) |