Sick sinus syndrome and orthostatic hypotension in Parkinson's disease

Pacemaker Implants and Their Influence on the Daily Life of Patients with Dementia with Lewy Bodies: A Qualitative Case Study

INTRODUCTION

Dementia with Lewy bodies (DLB) is an incurable form of dementia associated with detriments to the daily life of patients and carers from their family. Symptoms of orthostatic hypotension, syncope, and falls are supportive of DLB diagnosis. These symptoms may also be present among people with sick sinus syndrome (SSS), and subsequent pacemaker treatment to manage bradyarrhythmia is associated with improved cognitive function. The prevalence of SSS seems to be higher among people with underlying Lewy body pathology compared to the general age-matched population (5.2% vs. 0.17%). To our knowledge, how people with DLB and their family carers may experience pacemaker treatment to manage bradyarrhythmia has not been previously reported. Therefore, the aim of this study was to explore how people with DLB experience daily life following a pacemaker implant to manage associated symptoms of bradyarrhythmia.

METHODS

A qualitative case study design was used. Two men with DLB and their spouse carers were repeatedly interviewed as a dyad within 1 year following implant of a dual-chamber rate-adaptive (DDD-CLS) pacemaker to manage SSS in the men. Content analysis was used to assess the qualitative interview data collected.

RESULTS

Three categories emerged: (1) gaining control, (2) maintaining a social life, and (3) being influenced by concurrent diseases. Less syncope/falls and remote pacemaker monitoring increased a sense of control in everyday life, while perceived physical and/or cognitive improvements influenced social participation. The men were still affected by concurrent diseases, which continuously influenced each couple's daily life.

CONCLUSION

Identifying and managing concurrent bradyarrhythmia through a pacemaker implant could improve well-being for people with DLB.

Exploring the prevalence of undetected bradyarrhythmia in dementia with Lewy bodies

PURPOSE

To explore the prevalence of undetected bradyarrhythmia in a cohort of people with dementia with Lewy bodies.

METHODS

Thirty participants diagnosed with dementia with Lewy bodies were enrolled from three memory clinics in southern Sweden between May 2021 and November 2022. None had a history of high-grade atrioventricular block or sick sinus syndrome. Each participant underwent orthostatic testing, cardiac [123I]metaiodobenzylguanidine scintigraphy and 24-h ambulatory electrocardiographic monitoring. Concluding bradyarrhythmia diagnosis was obtained until the end of December 2022.

RESULTS

Thirteen participants (46.4%) had bradycardia at rest during orthostatic testing and four had an average heart rate < 60 beats per minute during ambulatory electrocardiographic monitoring. Three participants (10.7%) received a diagnosis of sick sinus syndrome, of whom two received pacemaker implants to manage associated symptoms. None received a diagnosis of second- or third-degree atrioventricular block.

CONCLUSION

This report showed a high prevalence of sick sinus syndrome in a clinical cohort of people with dementia with Lewy bodies. Further research on the causes and consequences of sick sinus syndrome in dementia with Lewy bodies is thus warranted.

Classical and Delayed Orthostatic Hypotension in Patients With Unexplained Syncope and Severe Orthostatic Intolerance

Background: Orthostatic hypotension (OH) is a major sign of cardiovascular autonomic failure leading to orthostatic intolerance and syncope. Orthostatic hypotension is traditionally divided into classical OH (cOH) and delayed OH (dOH), but the differences between the two variants are not well-studied. We performed a systematic clinical and neuroendocrine characterization of OH patients in a tertiary syncope unit.

Methods: Among 2,167 consecutive patients (1,316 women, 60.7%; age, 52.6 ± 21.0 years) evaluated for unexplained syncope and severe orthostatic intolerance with standardized cardiovascular autonomic tests including head-up tilt (HUT), we identified those with a definitive diagnosis of cOH and dOH. We analyzed patients' history, clinical characteristics, hemodynamic variables, and plasma levels of epinephrine, norepinephrine, C-terminal-pro-arginine-vasopressin (CT-proAVP), C-terminal-endothelin-1, mid-regional-fragment of pro-atrial-natriuretic-peptide and pro-adrenomedullin in the supine position and at 3-min HUT.

Results: We identified 248 cOH and 336 dOH patients (27% of the entire cohort); 111 cOH and 152 dOH had blood samples collected in the supine position and at 3-min HUT. Compared with dOH, cOH patients were older (68 vs. 60 years, p < 0.001), more often male (56.9 vs. 39.6%, p < 0.001), had higher systolic blood pressure (141 vs. 137 mmHg, p = 0.05), had lower estimated glomerular filtration rate (73 vs. 80 ml/min/1.73 m², p = 0.003), more often pathologic Valsalva maneuver (86 vs. 49 patients, p < 0.001), pacemaker-treated arrhythmia (5 vs. 2%, p = 0.04), Parkinson's disease (5 vs. 1%, p = 0.008) and reported less palpitations before syncope (16 vs. 29%, p = 0.001). Supine and standing levels of CT-proAVP were higher in cOH (p = 0.022 and p < 0.001, respectively), whereas standing norepinephrine was higher in dOH (p = 0.001). After 3-min HUT, increases in epinephrine (p < 0.001) and CT-proAVP (p = 0.001) were greater in cOH, whereas norepinephrine increased more in dOH (p = 0.045).

Conclusions: One-quarter of patients with unexplained syncope and severe orthostatic intolerance present orthostatic hypotension. Classical OH patients are older, more often have supine hypertension, pathologic Valsalva maneuver, Parkinson's disease, pacemaker-treated arrhythmia, and lower glomerular filtration rate. Classical OH is associated with increased vasopressin and epinephrine during HUT, but blunted increase in norepinephrine.