CPAP telemonitoring can track Cheyne-Stokes respiration and detect serious cardiac events: The AlertApnée Study.

BACKGROUND AND OBJECTIVE: Case reports have suggested that continuous positive airway pressure (CPAP) telemonitoring can detect the onset of acute cardiac events such as decompensated heart failure (HF) or atrial fibrillation through an increase in the apnoea-hypopnoea index (AHI) and onset of Cheyne-Stokes Respiration (CSR). This study addressed whether long-term remote CPAP treatment telemonitoring revealing CSR can help detect serious cardiac events (SCEs) in obstructive sleep apnoea (OSA) patients. METHODS: This monocentric prospective cohort study included adults receiving CPAP therapy for OSA with daily telemonitoring. Any sudden increase in AHI generated an alert for the home healthcare provider to download CPAP data to identify CSR. A medical consultation was scheduled if CSR was detected. RESULTS: We included 555 adults (412 men; 57% with known cardiovascular comorbidities). During the 1-year follow-up, 78 CSR episodes were detected in 74 patients (CSR+). The main conditions associated with incident CSR were HF (24 patients [30.8%]), ventilatory instability (21, 26.9%), leaks (13, 16.7%), medications inducing central apnoeas (baclofen, ticagrelor, opioids) (7, 9.0%), arrhythmias (6, 7.7%) and renal failure (2, 2.6%). Fifteen (20.3%) CSR+ patients had a confirmed SCE. In univariable analysis, a CSR episode increased the risk of an SCE by 13.8-fold (5.7-35.6) (p < 0.0001), with an adjusted OR of 5.7 (2.0-16.8) in multivariable analysis. CONCLUSION: Long-term telemonitoring of patients on CPAP treatment can alert CSR episodes and allows early detection of SCEs in patients with or without known cardiac comorbidities.

Importance of ventricular longitudinal function in chronic heart failure.

AIMS: Despite its immediate relevance, cardiopulmonary exercise testing (CPET) is infrequently performed in the presence of chronic heart failure (CHF). Previous studies of patients suffering from CHF have found a closer correlation between exercise capacity and measurements of diastolic than systolic ventricularfunction. We examined the correlation between echocardiographic measurements and (i) results of CPET and (ii) cardiovascular prognosis. METHODS AND RESULTS: We performed resting two-dimensional echocardiograms and CPET in 140 patients with CHF (mean age = 61 ± 13 years, 111 men). The underlying heart disease was ischaemic in 48 patients (34%). They were followed for a mean of 38 months (range 28-52). The mean left ventricular (LV) ejection fraction (EF) was 30 ± 9% and peak VO2 17.2 ± 6.5 mL/kg/min. LVEF correlated weakly with peak VO2 (r = 0.21), while systolic and early diastolic LV longitudinal function correlated best [early diastolic peak velocity at the mitral annulus (E'): r = 0.38; global longitudinal strain (GLS): r = -0.4; P <0.001 for both]. By multiple variable regression analysis, the best prediction of peak VO2 was derived from a model based on age, mitral annulus end-diastolic peak velocity (A'), GLS, right ventricular (RV) systolic strain, and left atrial systolic strain (r² = 0.57; P <0.0001). The two best independent predictors of adverse cardiovascular events at 28 months were GLS (odds ratio 1.31, P <0.001; prognostic cut-off = -8%) and RV systolicstrain (odds ratio 1.05, P =0.01; prognostic cut-off = -22%). CONCLUSION: Resting RV and LV longitudinal functions were reliable predictors of adverse cardiovascular events and correlated moderately with, but not took to the place of, CPET measurements.

Takotsubo cardiomyopathy associated with Guillain-Barré syndrome: a differential diagnosis from dysautonomia not to be missed.

A 60-year-old woman presented with a 1-week progressive limb weakness and an areflexic tetraparesis. Both neurophysiological and cerebrospinal fluid examinations were consistent with diagnosis of Guillain-Barré syndrome (GBS) and a treatment by intravenous immunoglobulin over a 5-day period was started. At the end of the treatment, the patient suffered from an acute coronary syndrome (ACS) without stenosis at coronary arteriography. Left ventriculography showed segmental wall motion abnormalities with apical akinesis contrasting with hyperkinesis in basal segments, with a depressed left ventricular ejection fraction at 45%. Cardiac magnetic resonance imaging excluded the diagnosis of myocarditis. A diagnosis of "transient left ventricular apical ballooning syndrome" or "Takotsubo" syndrome was then made and a treatment by angiotensin-converting enzyme inhibitor and beta-blocker was introduced. Left ventricular dysfunction and electrocardiogram normalized within two weeks and the patient remained free from cardiovascular events at one year of follow-up. This cardiomyopathy is a recently known and now commonly diagnosed reversible systolic dysfunction mimicking ACS and is secondary to physical or emotional stress affecting mainly post-menopausal women. Electrocardiographic and echocardiographic abnormalities are often regressive in days or weeks, and rarely responsible for complications. This observation supports clinical evidence that electrocardiographic changes in GBS can be linked to Takotsubo syndrome, by means of the stressful trigger of GBS occurrence. This reversible cardiomyopathy needs adequate management and specific therapeutic strategies. Therefore, trans-thoracic echocardiography should be systematically performed when repolarisation abnormalities are present in this disease to rule out a Takotsubo syndrome, even in asymptomatic patients.