Parkinson's disease and cardiovascular involvement: Edifying insights (Review)

Parkinson's disease (PD) is one of the most common neurodegenerative illnesses, and is a major healthcare burden with prodigious consequences on life-quality, morbidity, and survival. Cardiovascular diseases are the leading cause of mortality worldwide and growing evidence frequently reports their co-existence with PD. Cardiac dysautonomia due to autonomic nervous system malfunction is the most prevalent type of cardiovascular manifestation in these patients, comprising orthostatic and postprandial hypotension, along with supine and postural hypertension. Moreover, many studies have endorsed the risk of patients with PD to develop ischemic heart disease, heart failure and even arrhythmias, but the underlying mechanisms are not entirely clear. As importantly, the medication used in treating PD, such as levodopa, dopamine agonists or anticholinergic agents, is also responsible for cardiovascular adverse reactions, but further studies are required to elucidate the underlying mechanisms. The purpose of this review was to provide a comprehensive overview of current available data regarding the overlapping cardiovascular disease in patients with PD.

Inappropriate Sinus Tachycardia: Etiology, Pathophysiology, and Management: JACC Review Topic of the Week

Inappropriate sinus tachycardia (IST) is a clinical syndrome that generally affects young patients and is associated with distressing symptoms. Although the most common symptom is palpitations, it can be accompanied by a myriad of symptoms, including anxiety, dizziness, presyncope, and syncope. The pathogenesis of IST is not well understood and considered multifactorial, with autonomic dysfunction being the central abnormality. IST is a diagnosis of exclusion. Management presents a clinical challenge. The overall efficacy of lifestyle modifications and medical therapy may be limited. Recent advances in catheter and surgical sinus node sparing ablation techniques have led to improvement in outcomes. In addition, increased focus has led to development of multimodality team-based interventions to improve outcomes in this group of patients. In this review, we discuss the mechanistic basis of IST, review current approaches to diagnosis, and outline contemporary therapeutic approaches.

Cardiac Dysautonomia Predicts Long-Term Survival in Hereditary Transthyretin Amyloidosis After Liver Transplantation

OBJECTIVES

This study sought to compare techniques evaluating cardiac dysautonomia and predicting the risk of death of patients with hereditary transthyretin amyloidosis (mATTR) after liver transplantation (LT).

BACKGROUND

mATTR is a multisystemic disease involving mainly the heart and the peripheral nervous system. LT is the reference treatment, and pre-operative detection of high-risk patients is critical. Cardiovascular dysautonomia is commonly encountered in ATTR and may affect patient outcome, although it is not known yet which technique should be used in the field to evaluate it.

METHODS

In a series of 215 consecutive mATTR patients who underwent LT, cardiac dysautonomia was assessed by a dedicated clinical score, time-domain heart rate variability, ¹²³-meta-iodobenzylguanidine heart/mediastinum (¹²³-MIBG H/M) ratio on scintigraphy, and heart rate response to atropine (HRRA).

RESULTS

Patient median age was 43 years, 62% were male and 69% carried the Val30Met mutation. Cardiac dysautonomia was documented by at least 1 technique for all patients but 6 (97%). In univariate analysis, clinical score, ¹²³-MIBG H/M ratio and HRRA were associated with mortality but not heart rate variability. The ¹²³-MIBG H/M ratio and HRRA had greater area under the curve (AUC) of receiver-operating characteristic curves than clinical score and heart rate variability (AUC: 0.787, 0.748, 0.656, and 0.523, respectively). Multivariate score models were then built using the following variables: New York Heart Association functional class, interventricular septum thickness, and either ^123-MIBG H/M ratio (S_MIBG) or HRRA (S_atropine). AUC of S_MIBG and S_atropine were greater than AUC of univariate models, although nonsignificantly (AUC: 0.798 and 0.799, respectively). Predictive powers of S_MIBG, S_atropine, and a reference clinical model (AUC: 0.785) were similar.

CONCLUSIONS

Evaluation of cardiac dysautonomia is a valuable addition for predicting survival of mATTR patients following LT. Among the different techniques that evaluate cardiac dysautonomia, ¹²³-MIBG scintigraphy and heart rate response to atropine had better prognostic accuracy. Multivariate models did not improve significantly prediction of outcome.

Modeling and imaging cardiac sympathetic neurodegeneration in Parkinson's disease

Parkinson's disease (PD) is currently recognized as a multisystem disorder affecting several components of the central and peripheral nervous system. This new understanding of PD helps explain the complexity of the patients' symptoms while challenges researchers to identify new diagnostic and therapeutic strategies. Cardiac neurodegeneration and dysautonomia affect PD patients and are associated with orthostatic hypotension, fatigue, and abnormal control of electrical heart activity. They can seriously impact daily life of PD patients, as these symptoms do not respond to classical anti-parkinsonian medications and can be worsened by them. New diagnostic tools and therapies aiming to prevent cardiac neurodegeneration and dysautonomia are needed. In this manuscript we critically review the relationship between the cardiovascular and nervous system in normal and PD conditions, current animal models of cardiac dysautonomia and the application of molecular imaging methods to visualize cardiac neurodegeneration. Our goal is to highlight current progress in the development of tools to understand cardiac neurodegeneration and dysautonomia and monitor the effects of novel therapies aiming for global neuroprotection.

The Phantom in our opera - or the hidden ways of the autonomic nervous system in cardiac patients

The role of the autonomic nervous system in the understanding of pathophysiological mechanisms in a variety of cardiovascular clinico-pathological conditions is highlighted from a clinician's point of view with the focus on coronary mimicry, enhanced sympathetic tone and syndrome X. A unique case is presented where sinus node dysfunction in pandysautonomia seemed to be an early sign of hypothalamic glioblastoma. In addition, relevant literature on this topic is addressed to put distinct clinical patterns into a broader perspective.