Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0012833 (dizziness)
 9,689 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

To investigate whether the preservation of atrioventricular (AV) synchronization matters for quality-of-life during pacemaker treatment we assessed 17 consecutive patients with high degree AV block and preserved sinus node function in a double-blind, long-term crossover study. A questionnaire with regard to cardiovascular symptoms, sleep disturbances, cognitive functioning, physical ability, social interaction, emotional functioning, and self-perceived health was completed after 2 months of atrial synchronous (DDD) and rate modulated ventricular pacing (VVI,R), respectively. A significant improvement in shortness of breath, dizziness and palpitations as well as an improvement of cognitive functioning was observed during DDD pacing. Nine patients preferred the DDD mode and three the VVI,R mode. The remaining five patients did not express any preference. The preference for the DDD mode was explained by a significant reduction of cardiovascular symptoms and an improved self-perceived health, physical ability, and psychological well-being during DDD pacing. All differences in quality-of-life parameters between the two modes of pacing favored the DDD mode and no adverse effects of this mode were found. Thus, the maintenance of AV synchrony adds further symptomatic relief compared to rate increase alone. The results indicate that DDD pacing is the preferred mode of pacing in patients with high degree AV block and preserved sinus node function.
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PMID:Quality-of-life in patients treated with atrioventricular synchronous pacing compared to rate modulated ventricular pacing: a long-term, double-blind, crossover study. 138 58

We examined, a 64 year old man with hypertrophic nonobstructive cardiomyopathy (HNCM) accompanied with dizziness. Twenty-four hour ECG monitoring showed sinus bradycardia and sinoatrial block. Electrophysiologic study demonstrated inducible sustained ventricular tachycardia (VT) by continuous rapid high right atrum pacing during which systolic blood pressure fell to 40 mmHg. Induced VT degenerated into ventricular fibrillation in ten seconds. We implanted a DDD pacemaker for sick sinus syndrome (SSS) and administrated 90mg/day of diltiazem for VT. Treadmill exercise test was carried out while the patient was taking diltiazem and no arrhythmia was induced. This case of HNCM is rare in that he presented both sick sinus syndrome and sustained VT.
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PMID:[A case of nonobstructive hypertrophic cardiomyopathy associated with ventricular tachycardia and sick sinus syndrome]. 143 57

In patients affected by high degree AV block without preexisting congestive heart failure there is no definite demonstration that DDD pacing gives real clinical advantages in respect to VVIR pacing. We performed an intrapatient, long-term study between the two pacing modes in 14 high degree AV block patients, using the Medtronic Synergyst 7027 dual chamber pacemaker, who could be programmed alternatively in DDD or VVIR mode. After a 4-week run-in period following the pacemaker implant, patients completed a randomized, double-blind, cross-over study to compare the effect of 6-week period VVIR and DDD pacing on symptoms and cardiovascular parameters. A semiquantitative score scale was used to quantify the symptoms of general well-being, palpitations, dizziness, pulsating sensation in the neck or abdomen, shortness of breath at rest and during effort, chest pain, and NYHA classification. The sum of symptom scores was 10.4 +/- 6.7 in VVIR period and 4.6 +/- 2.7 in DDD period (P less than 0.001); five patients (36%) crossed over early from VVIR to DDD because of intolerable symptoms; overall, eight patients preferred the DDD mode and no one preferred the VVIR. Cardiac output at rest (echo-Doppler method) was 4.7 +/- 1.4 versus 5.7 +/- 1.6 liter/min (P less than 0.01), body weight was 65.9 +/- 6.6 versus 64.9 +/- 6.1 kg (P less than 0.02), atrial natriuretic peptide was 236 +/- 112 versus 198 +/- 110 pg/mL (P less than 0.01), respectively, during VVIR and DDD modes. Effort tolerance was similar with the two modes of pacing (68 +/- 15 vs 70 +/- 18 watts/min).(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Intrapatient comparison between chronic VVIR and DDD pacing in patients affected by high degree AV block without heart failure. 170 47

A new method for selection of the pacing mode in 60 consecutive patients with severe cardioinhibitory or mixed carotid sinus syndrome was prospectively validated. DDD pacing was preferred for 26 patients with: (1) the cardioinhibitory form and who had symptomatic pacemaker effect; (2) mixed type I form, (cardioinhibitory and vasodepressor) with symptomatic pacemaker effect, ventriculoatrial conduction or orthostatic hypotension; (3) mixed type II; or (4) severe bradycardia. VVI pacing was selected in the remaining 34 patients without these symptoms. During a 32 +/- 10 month follow-up period syncope and severe dizziness persisted in five patients in the VVI group (15%) and in three patients in the DDD group (12%). Symptomatic relief occurred in 87% (52/60) of patients. Minor symptoms persisted in 47% of the VVI group and 42% of the DDD group. No patient developed cardiac insufficiency or intolerance to pacing. During a 2-month duration a single-blind, randomized, cross-over study compared VVI and DDD pacing, 69% of the patients programmed from DDD to VVI suffered more frequent, severe, and intolerable symptoms. (1) Thirty four of 60 patients (57% of the entire group) in whom VVI pacing was satisfactory were identified prior to pacemaker implant. In the remainder, VVI pacing was contraindicated as it produced frequent side effects. (2) The preimplant predictive value that VVI pacing would be successful was 85% for those eventually receiving VVI pacemakers and the preimplant predictive value that VVI pacing would fail was 69% for those who underwent DDD implant.
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PMID:Validation of a method for choice of pacing mode in carotid sinus syndrome with or without sinus bradycardia. 170 5

Fifteen patients with dual chamber pacemakers implanted for atrioventricular block (11) or sinoatrial disease (4) completed a single blind within-patient comparison of symptoms and 24 hour intra-arterial blood pressure during long term atrioventricular synchronous (DDD) pacing and long term ventricular demand (VVI) pacing. The patients reported significantly less breathlessness, fatigue, and dizziness and a significantly greater sense of general well-being during DDD pacing than during VVI pacing. Twelve of the fifteen patients expressed a strong preference for DDD pacing. Systolic blood pressure tended to be lower and was significantly more variable during VVI pacing than during DDD pacing (mean (SD) daytime systolic blood pressure 132.4 (17.1) and 140.4 (13.1) mm Hg respectively). Accordingly, episodes of hypotension were more common during VVI pacing, which may partly explain why the patients reported more symptoms during this mode of pacing.
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PMID:A comparison of symptoms and intra-arterial ambulatory blood pressure during long term dual chamber atrioventricular synchronous (DDD) and ventricular demand (VVI) pacing. 330 70

A permanent pacemaker was inserted in eight patients with the long QT syndrome. All had recurrent syncope or seizures, six had documented torsade de pointes and four had aborted sudden death. Among the eight patients, permanent pacing was instituted in three who were unsuccessfully treated with both a beta-adrenergic blocking agent and left cardiothoracic sympathectomy, and in two who proved refractory or intolerant to beta-blockers. Another three patients had pacemaker implantation and long-term beta-blocker therapy because of spontaneous atrioventricular (AV) block in one, aborted sudden death in one and patient preference in one. After pacing (70 to 85 beats/min), there was no significant change in the mean corrected QT interval, but the mean QT interval decreased significantly (534.4 +/- 51.4 to 425.6 +/- 18.9 ms, p less than 0.0001). Over a mean follow-up period of 35.1 +/- 18.9 months, all patients are alive and currently free of syncope. One patient without a history of stress-induced syncope had two syncopal episodes (believed to be due to hyperventilation) while under severe emotional stress, but has been symptom free for the past 5 years. One patient with an atrial demand (AAI) pacemaker developed dizziness due to documented episodes of AV block, but remains asymptomatic after conversion to atrial rate-responsive dual chamber (DDD) pacing. Either atrial or ventricular pacing combined with beta-blocker therapy appears to be effective treatment for a subset of patients with the long QT syndrome, by either preventing episodes of torsade de pointes or alleviating symptoms due to bradycardia from beta-blocker therapy.
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PMID:Permanent cardiac pacing in patients with the long QT syndrome. 362 66

A within patient double blind prospective study of symptoms and exercise tolerance was designed to determine the preferred pacing mode in 10 patients with programmable dual chamber pacemakers who also had angina pectoris. Patients were randomly allocated to one month in each of the following modes: ventricular pacing at 70 beats/min (VVI) or atrioventricular synchronous upper rate 150 beats/min (DDD 150) or 100 beats/min (DDD 100). Medications were unchanged throughout the study; none was taking beta blockers. At the end of each month patients underwent an exercise test. During each month patients recorded symptoms and their preferred pacing mode. DDD 100 was the preferred mode (seven patients). There was significantly less chest pain with this mode than with either of the other modes. There were significantly more episodes of dizziness in VVI, and two patients who developed pacemaker syndrome were unable to complete the pacing period. Three patients developed angina during exercise testing in DDD 150. Atrial synchronous ventricular pacing is better than ventricular pacing for the control of symptoms in patients with angina pectoris provided that the upper atrial tracking rate is limited.
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PMID:Optimum pacing mode for patients with angina pectoris. 379 Mar 82

A 45-year-old man who had been implanted with a VVI pacemaker for sinus arrest complained of syncope, dizziness and throbbing in the neck. His pacemaker function was normal, but during ventricular pacing, retrograde V-A conduction was observed. This pacer was replaced by a DVI unit which caused periodic abdominal muscular contractions. We replaced this unit with an Intermedics Cosmos DDD-M pacemaker. This type of pacemaker in a patient with V-A conduction may cause pacemaker-mediated tachycardia (PMT). However, the Cosmos has a tachycardia-termination algorithm which detects continued pacing at the ventricular tracking rate, allows it to proceed for 15 consecutive pace events, and inhibits the 16th ventricular output pulse, thus breaking the reentry loop. The Cosmos pacer has a number of features to prevent initiation of PMT, and is also able to terminate the tachycardia when it occurs because of the tachycardia-termination algorithm. This feature is valuable in DDD-M pacemakers implanted in patients with V-A conduction. Whether this algorithm will be effective in all cases remains to be determined.
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PMID:Tachycardia-termination algorithm: a valuable feature for interruption of pacemaker-mediated tachycardia. 620 Aug 58

In a prospective study, reentry tachycardias (RT) due to retrograde VA-conduction were sought in 30 patients after implantation of an atrial synchronous (VDD, DDD) pacemaker (PM) by frequent clinical controls and by 24-hour Holter monitoring. At least one RT was detected in 9/30 patients (in 5 during clinical control, in 4 on Holter monitoring only). 6 patients had symptoms due to RT (6 had palpitations, 1 complained of dizziness and 1 of ischemic heart pain). RTs were initiated by VPBs in 6 patients, by sinus bradycardia in 2 (VDD) and by magnet application in 1. Rates of RT varied from 100 bpm to 128 bpm. RT necessitated reprogramming of the PM in 5 patients (in 3 of them reprogramming to VVI-stimulation). RTs are thus a frequent complication after implantation of an atrial synchronous pacemaker.
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PMID:[Re-entry tachycardias: a fragment problem during physiologic heart stimulation]. 665 11

The unipolar pulse generator systems were tested in 220 patients (96 VVIM, 97 VVIO, 27 physiological systems) to determine the incidence of sensing interference with muscle potentials. 23% exhibited oversensing, with a sex distribution of 32% for males and 15% for females. The interference was observed more often in VVIM pacemakers at nominal setting (35%) than in VVIO pacemakers (11%). In DDD pacemakers both inhibition and triggering of ventricular stimulation was observed. Among the 23 patients with persisting syncope or dizziness after implantation of the pacemaker, the symptoms were observed during physical activity only in 5. In these 5 the underlying arrhythmia was tachycardia in 3 and inhibition of the pacemaker by muscle potentials in only one patient.
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PMID:[Inhibition and triggering of heart pacemakers by muscle potentials]. 715 53


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