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Query: UMLS:C0038454 (stroke)
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A total of 1,431 patients (mean age 63.4 +/- 14.1) with pacemakers (96.2% VVI) primoimplanted between 1967 and 1985 were followed for a mean duration of 78.2 +/- 40 pacing months, with 0.6% loss to follow-up. Cumulative survival for 1, 3, and 10 years was 0.9427, 0.9136, and 0.7536, respectively. There was no significant difference in survival between atrioventricular block (AVB) and sick sinus syndrome (SSS) patients. In addition to age and gender, factors existent prior to implantation that independently affected prognosis included manifest coronary heart disease (CHD), congenital/acquired heart lesions, heart failure, noncardiac internal disease, syncope, and generalized fatigue. After implantation, the most important factor was generalized fatigue, then age, stroke, myocardial infarct (MI), gender (male), heart failure, and syncope. Patients with no underlying disease showed an extremely high cumulative survival (0.9173 at 10 years). Compared to the general population of Yugoslavia, the pacemaker patients showed a similar yearly mortality rate until 1981. After that, elderly males (70+) had a significantly lower yearly mortality than the matched population. Thus, in this large series of pacemaker patients followed into the most recent period with an extremely low loss to follow-up, short- and long-term survival was very high. Pacemaker patients of any age who are otherwise in good health have an excellent prognosis.
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PMID:Survival in 1,431 pacemaker patients: prognostic factors and comparison with the general population. 137 12

Our review of the current literature and experience in caring for pacemaker patients suggests that a consideration of hemodynamics is a logical way to approach pacemaker selection and programming. Multiple clinical factors enter into the selection of a pacemaker or pacemaker programming settings in each case. It appears that in patients with sinus node disease, atrial-inhibited or dual-chamber pacing provides the best chance for preventing the development of chronic atrial fibrillation with its attendant risks of embolism and stroke. It is clear that AV synchrony has beneficial hemodynamic effects at rest in most patients. The results of Labovitz would suggest that in patients with marked left atrial enlargement, this may be less so. The results of Stewart et al would further suggest that in patients with retrograde VA conduction, dual-chamber pacing is preferable. Retrograde VA conduction can be intermittent and this makes it difficult to use its absence on a single test to decide on the type of pacemaker to use. It appears that baseline left ventricular function does not determine the relative improvement in cardiac output observed with AV synchrony or rate-adaptive pacing. However, in patients with severe congestive heart failure even a small improvement in cardiac output may result in significant clinical improvement. Studies have shown that in any given patient, there may be an optimal AV interval at rest. In general, this ranges from 100 to 150 milliseconds. In normal individuals the optimal AV interval shortens with increased heart rate during exercise in a predictable and linear fashion. The hemodynamic benefits of a shortened AV interval with faster heart rates in pacemaker patients have not yet been shown. Intuitively, however, this would appear to be a desirable approach and will probably be added to the design of future generations of dual-chamber pacemakers. Studies of the effect of different pacing modes on secretion of atrial natriuretic factor are intriguing and may contribute more to our understanding of pacing hemodynamics in the future. During exercise, heart rate increase is more important than AV synchrony and this has been shown by several studies. Thus, in active patients with chronotropic incompetence due to sick sinus syndrome, the addition of rate-adaptive pacing is important. Because single-chamber rate-adaptive atrial pacing leaves the patient exposed to the risk of future development of AV block and DDD pacing does not provide chronotropic support, it is likely that the new rate-adaptive dual-chamber (DDDR) devices will be used in a significant number of these patients.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:Pacemaker hemodynamics: clinical implications. 154 30

To assess the hemodynamic consequences associated with ventriculoatrial (VA) conduction following pacemaker implantation, 22 subjects with the sick sinus syndrome were studied using two-dimensional echocardiography (2DE) and Doppler techniques, including pulsed Doppler (PD). Pacemakers used were unipolar, programmable pulse generators which can operate in the DDD and VVI modes. A simultaneous strip chart recording of 2DE, phonocardiogram and ECG was obtained in each mode. Systolic time intervals (STI) and left ventricular diameters were measured using 2DE. Left ventricular ejection time (LVET) was determined from the aortic valve echo, which was the interval between the opening and closure of the cusp. Left ventricular pre-ejection period (LVEPEP) was the interval between the Q wave of the ECG and the opening of the aortic valve. Right ventricular (RV) STI were also measured using the pulmonary valve echo in a manner similar to that used with the aortic valve echo. Stroke volume and ejection fraction were calculated by conventional methodology. RVET was longer than LVET; RVPEP was shorter than LVPEP. These two STIs were shortened using an incremental pacing rate in each mode. Similarly, the stroke volume and ejection fraction decreased, depending on the pacing rate at a range of 50-110 b/min. RVET and LVET in DDD were longer than those in VVI. RVPEP and LVPEP in DDD were shorter than those in VVI. Stroke volume and ejection fraction in DDD were smaller than those in VVI. There was a significant difference (p less than 0.05) between DDD and VVI. These differences became significantly (p less than 0.01) greater between DDD without VA conduction and VVI with VA conduction.(ABSTRACT TRUNCATED AT 250 WORDS)
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PMID:[Influence of ventriculoatrial conduction on hemodynamic consequences in patients with artificial pacing]. 213 61

Difference of cardiac output and stroke volume between that in DDD and that in VVI was studied by pulsed Doppler echocardiography at different pacing rates. Moreover, to evaluate the usefulness of the method by pulsed Doppler echocardiography, cardiac output by the Swan-Ganz catheter method was measured and compared. Fourteen patients age 37-83 years (mean 65 years) with sick sinus syndrome and implanted multiprogrammable dual chamber pacemakers were studied. Cardiac output was measured as the product of the echocardiographically determined cross sectional area of the aortic anulus and the Doppler-determined mean velocity of left ventricular outflow over systole. Cardiac output was greater in DDD with atrial kick than in VVI at each pacing rate, and increased with elevation of the rate, but it was smaller at 120 PPM than at 110 PPM in DDD. Stroke volume was greater in DDD than in VVI at each pacing rate, and maximum volume was at 60 PPM in both modes. The data by pulsed Doppler echocardiography and by Swan-Ganz catheter method have high correlation. Besides being related with pulse rate, these results may be related with such things as myocardial contractility, preload and afterload. For example, the tension of autonomic nervous system, the changing of venous return volume, the disease of arteriosclerosis and old myocardial infarction, temperature, blood viscosity and so on. We will continue the study considering these factors.
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PMID:[Comparison of cardiac output between in DDD and in VVI by pulsed Doppler echocardiographic method (correction with Swan-Ganz catheter method)]. 226 68

To evaluate the effects of atrioventricular pacing interval on hemodynamics, we studied the changes in stroke volume and left ventricular filling dynamics in fourteen consecutive patients with implanted atrioventricular pacemakers using a Doppler echocardiographic technique. Twelve patients had sick sinus syndrome and 2 had complete atrioventricular block. Stroke volume was determined as the time-velocity integral of the pulsed Doppler recordings at the aortic annulus multiplied by the area of the aortic annulus obtained by 2-dimensional echocardiography. Left ventricular filling velocity was measured at the mitral annulus by the pulsed Doppler technique to provide the time-velocity integral of rapid filling (TVI-R) and that of atrial filling (TVI-A). No significant change in stroke volume was noted during the atrioventricular interval manipulation. TVI-R was greater with short atrioventricular intervals than that with the long atrioventricular intervals. On the contrary, TVI-A was greater with long atrioventricular intervals than that with short atrioventricular intervals. These results suggested that there is a compensatory mechanism in the left ventricular filling dynamics to keep the stroke volume constant despite the change in the atrioventricular interval. However, in patients with high atrial filling to rapid filling ratio (A/R), the stroke volume varied with change of atrioventricular interval, suggesting that the compensatory mechanism was not sufficient in such patients. We conclude that Doppler echocardiography is a useful, noninvasive technique to assess the changes in the hemodynamics produced by atrioventricular interval manipulation in patients with implanted atrioventricular pacemakers.
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PMID:[Noninvasive evaluation of changes in stroke volume and left ventricular filling dynamics. Produced by atrioventricular interval manipulation]. 261 8

To evaluate the mechanism of sudden death in childhood and the physical activity levels at the onset of sudden death, we studied the following items: (1) the incidence and the circumstances surrounding sudden death at school in Kanagawa Prefecture, (2) high risk heart diseases detected among healthy school children by heart disease screening, (3) sudden cardiac death or near miss seen in outpatients with heart disease except congenital heart disease. Among total 15,156,346 school children, sudden death was observed in 97 subjects (M:77, F:20). Annual incidence of sudden death was 6.4 per 10(6). Of the 97 subjects, acute heart failure of unknown etiology was found in 60 (62%), cardiovascular disease in 18 (19%), cerebral vascular accidents in 14 (14%) and heat stroke in 5 (5%). Of the 78 subjects (M:64, F:14) considered as sudden cardiac death, 62 (79%) died during sports activities, and 16 (21%) died at rest. Of the 62 subjects, 29 died during track and field activities and 7 while swimming, both in physical education classes. Eighteen died during athletic club activities and 8 during extracurricular activities. Consequently, 54 subjects (87%) died in the presence of a school teacher. Of the 18 subjects with cardiovascular disease, 9 (hypertrophic cardiomyopathy in 3, myocarditis in 3, Kawasaki disease in 2 and long QT in one) were diagnosed initially by the autopsy study. Latent high risk heart diseases, detected among presumably healthy school children by the heart disease screening program, were the following: hypertrophic cardiomyopathy, long QT syndrome, Kawasaki disease and some arrhythmias (ventricular tachycardia, sick sinus syndrome, A-V block and atrial fibrillation). Follow-up observations of outpatients with heart disease revealed the same results as the heart disease screening program. In order to prevent sudden death at school, the following recommendations should be observed: 1) sports directors should learn "sports medicine in childhood", including primary cardiovascular resuscitation, 2) an accurate heart disease screening program should be operated to detect latent high risk heart diseases, advise on adequate medical treatment, and help ensure an appropriate selection of sports activities, 3) comprehensive autopsy studies should be performed.
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PMID:Sudden cardiac death in childhood. 263 28

The results of Holter monitoring in 100 patients with transient and focal cerebral ischemia were studied retrospectively. Atrial fibrillation (AF) was found in five patients compared with two from a group of 100 age and sex-matched control patients. Four of these had a previous history of AF or showed AF on the standard electrocardiogram. Episodic forms of sick sinus syndrome, which have also been related to cerebral embolism, were found in 32 of the TIA patients against 13 of the controls (p less than 0.0025). Sick sinus syndrome was of the bradyarrhythmia-tachyarrhythmia type in 14 of the TIA patients and in three of the controls (p less than 0.01). The relationship between TIAs and transient sinus node dysfunction could not be explained by concomitant heart disease. It is not yet clear whether the relationship is causal or indirect.
Stroke
PMID:Holter monitoring in patients with transient and focal ischemic attacks of the brain. 293 8

The risk of embolic stroke during sick sinus syndrome before cardiac pacemaker insertion is substantial, but stroke after pacemaker insertion has not been well studied. We observed 10 sick sinus syndrome patients who developed an ischemic stroke 4 days to 112 months after pacemaker insertion. Nine patients represented 6% of the 156 ischemic stroke patients observed during a 30-month period. Eight had a ventricular-demand pacemaker, one had a dual-chamber pacemaker, and one had an atrial-inhibited pacemaker. Six patients were in atrial fibrillation at stroke onset, but none had atrial fibrillation when the pacemaker was inserted. Six patients were taking aspirin, and one was anticoagulated when stroke occurred. Stroke in sick sinus syndrome after pacemaker insertion is not rare, and pacing does not appear to be protective. Sick sinus syndrome patients who convert to atrial fibrillation or who have a ventricular-demand pacemaker might represent high-risk groups for stroke.
Stroke 1988 Jun
PMID:Ischemic stroke after cardiac pacemaker implantation in sick sinus syndrome. 337 62

Incidence, clinical picture, ECG features, as well as chosen diagnostic and therapeutic measures were investigated in patients attending the Basel University Medical Outpatients Department with the diagnosis of sick sinus syndrome. A retrospective study was conducted by selecting patients' charts with this diagnosis during the period 1979-1983. Forty-four patients (17 women, 27 men, mean age 64.5 +/- 14.5 years) were "discovered" and divided into three groups: Group 1: asymptomatic patients with pathological ECG (n = 7), Group 2: symptomatic patients with pathological ECG (n = 22), Group 3: main symptom syncope (n = 15). All patients had had an ECG and 15 a 24-hour-ECG. Carotid sinus massage was performed in three patients and sinus node recovery time was measured in another three. Seventeen patients remained without treatment, 13 received a permanent pacemaker, 9 of whom had additional medication, while 12 were anticoagulated. Three patients who were not anticoagulated suffered a stroke. More invasive electrophysiological investigations should be undertaken only with caution. In group 1, further diagnostic or therapeutic consequences need to be drawn. In the symptomatic patients from group 2, 24-hour-ECG is indicated when there is a history of palpitations, dizziness or severe heart failure. The immediate implantation of a pacemaker is justifiable in group 3 patients. Drugs with antiarrhythmic activity should be avoided in these patients before pacemaker implantation.
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PMID:[Sick sinus syndrome--clinical presentation, diagnostic and therapeutic measures in an ambulatory patient sample]. 398 2

One hundred and eighty-four consecutive patients admitted to an Investigative Stroke Unit with transient ischemic attacks (TIA) and cerebral infarction (stroke) had 48-hour automated arrhythmia monitoring, 55 patients had additional Holter monitoring and 127 patients had 2-D echocardiography. One hundred and sixteen presented with stroke (63%) and 68 patients with TIA (37%). One hundred and twenty-two were men (66.3%) and 62 were women (33.7%), mean age 63.5 years, range 25-86. The monitoring identified twelve (6.5%) patients with significant arrhythmias undetected by history, examination and admission electrocardiogram: six with atrial fibrillation (AF), four with 2 degrees heart block type Mobitz II and one each with 3 degrees heart block and sick sinus syndrome. Two-D echocardiography showed a previously unknown potential source for cardiac emboli in 22 patients (17.3%): segmental ventricular disease in eleven, mitral valve prolapse in seven, left ventricular thrombus in six, left ventricular aneurysm in three and one each with mitral valve endocarditis and global myocardial dysfunction. Only the mitral valve findings were expected on the basis of a previous M-mode echocardiographic study carried out in our city on healthy elderly volunteers. From the clinical history and all cardiac investigations, we found 59 patients (32%) with a possible cardiac source for cerebral emboli. After cerebral angiography, 29 of these 59 patients also showed a vascular lesion in the appropriate carotid artery and we could not decide definitely which lesion was responsible for the cerebral embolus. In the remaining 30 patients (16.4%), the evidence implicated the heart as the most likely source.(ABSTRACT TRUNCATED AT 250 WORDS)
Stroke
PMID:Value of cardiac monitoring and echocardiography in TIA and stroke patients. 408 26


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