Heart block in patients with sleep apnoea.
Explore the source record for details and available documents.
Adult↗
Biomedical subjects
J H Peter
Publications and source records attributed to J H Peter.
Heart block in patients with obstructive sleep apnoea: pathogenetic factors and effects of treatment.
Heart block during sleep has been described in up to 10% of patients with obstructive sleep apnoea. The aim of this study was to determine the relationship between sleep stage, oxygen desaturation and apnoea-associated bradyarrhythmias as well as the effect of nasal continuous positive airway pressure (nCPAP)/nasal bi-level positive airway pressure (nBiPAP) therapy on these arrhythmias in patients without electrophysiological abnormalities. Sixteen patients (14 males and two females, mean age 49.6+/-10.4 yrs) with sleep apnoea and nocturnal heart block underwent polysomnography after exclusion of electrophysiological abnormalities of the sinus node function and atrioventricular (AV) conduction system by invasive electrophysiological evaluation. During sleep, 651 episodes of heart block were recorded, 572 (87.9%) occurred during rapid eye movement (REM) sleep and 79 (12.1%) during nonrapid eye movement (NREM) sleep stages 1 and 2. During REM sleep, the frequency of heart block was significantly higher than during NREM sleep: 0.69+/-0.99 versus 0.02+/-0.04 episodes of heart block x min(-1) of the respective sleep stage (p<0.001). During apnoeas or hypopnoeas, 609 bradyarrhythmias (93.5%) occurred with a desaturation of at least 4%. With nCPAP/ nBiPAP therapy, apnoea/hypopnoea index (AHI) decreased from 75.5+/-39.6 x h(-1) to 3.0+/-6.6 x h(-1) (p<0.01) and the number of arrhythmias from 651 to 72 (p<0.01). We conclude that: 1) 87.9% of apnoea-associated bradyarrhythmias occur during rapid eye movement sleep; 2) the vast majority of heart block episodes occur during a desaturation of at least 4% without a previously described threshold value of 72%; and 3) nasal continuous positive airway pressure or nasal bi-level positive airway pressure is the therapy of choice in patients with apnoea-associated bradyarrhythmias.
Adult↗
Circadian reactions to nCPAP treatment.
To determine possible effects of apnea attacks on the spontaneous behavior of the circadian system (body temperature, sleeping behavior, vigilance), 11 patients with obstructive sleep apnea (OSA) were observed before therapy over a 24 h period under a special constant routine (bed-rest study) and again during therapy with nCPAP (nasal continuous positive airway pressure). Clinical indicators (polysomnographical, subjective sleep quality, etc.) indicated successful therapy. During the bed-rest study with nCPAP therapy, the 24 h amplitude of core temperature was found to be greater than the amplitude measured before therapy. Also, therapy decreased sleep disturbances at night and reduced daytime sleeping times. Consequently, the level of subjective vigilance was higher during the daytime during therapy. OSA attacks do not only impair sleep; they disturb the whole circadian system. This may also impair recuperation and sleep. Further research should test whether measurements of the spontaneous circadian system could have additional diagnostic value and whether the stabilization of the circadian system has therapeutic value.
Adult↗
[Cardiorespiratory polygraphy in differential diagnosis of respiratory insufficiency in patients after coronary artery bypass operation].
BACKGROUND: In intensive care medicine it is well established how to diagnose respiratory insufficiency caused by cardiopulmonary diseases. However, there is no consensus how to diagnose respiratory insufficiency which may be caused by extrapulmonary disturbances of the respiratory apparatus. PATIENTS AND METHODS: In 5 patients we performed postoperatively a cardio-respiratory polygraphy for 12 to 13 hours using Polymesam. This unit allows to record airflow, respiratory movements of the chest and abdomen, arterial oxygen saturation, heart rate, body position and EKG. RESULTS: The present case-series-study demonstrates that patients after arterio-coronary bypass surgery may present respiratory insufficiency caused by extrapulmonary disturbances of the respiratory apparatus (central and obstructive apnea and hyoponea). The respiratory insufficiency occurs during nighttime even when supplemental oxygen (2 to 3 1/min) is delivered. CONCLUSION: We conclude that the cardiopulmonary polygraphy for assessing respiratory insufficiency in patients after coronary bypass surgery is important, in order to avoid severe arterial hypoxemia which may produce cardiovascular instability in these patients.
Adult↗
[Effect of noninvasive ventilation on work of breathing in obesity].
BACKGROUND: Noninvasive ventilation with nose- or face-masks has been increasingly used in the past. The objective of mechanical ventilation is in addition to improve gas exchange to reduce breathing work. While improvement on breathing work has been shown mainly on normal-weight patients with different respiratory diseases, there is no existing data about the effect of noninvasive ventilation on the breathing work of patients with massive obesity. PATIENTS AND METHODS: Assisted mask-ventilation with bilevel positive airway pressure (BiPAP) was carried out on 5 overweight control subjects (overweight controls), 7 overweight patients with obstructive sleep apnea (OSA), 6 patients with obesitas-hypoventilation syndrome (OHS), and 7 overweight patients with chronic obstructive lung disease (COLD). Inspiratory pressure assist (IPAP) was set to 12 or 16 cm H2O, exspiratory pressure (EPAP) was set to 5 cm H2O. All, subjects were massive overweight (body mass index [BMI] 42.2 +/- 5.8; range 31.8 to 55.4 kg/m2). Respiratory muscle activity was measured as esophageal pressure change (delta Pes) and transdiaphragmatic pressure change (delta Pdi) and calculated as pressure time integral. RESULTS: With noninvasive ventilation respiratory muscle activity was significantly (p < 0.05) reduced in all groups at least 40% compared to baseline values during spontaneous respiration. CONCLUSIONS: Noninvasive ventilation via face masks can efficiently reduce work of breathing in subjects with massive obesity.
Adult↗
[Work of breathing in noninvasive proportional assist ventilation in patients with respiratory insufficiency].
BACKGROUND: The aim of the present study was to evaluate if Proportional Assist Ventilation (PAV), when applied noninvasively via face mask, can reduce ventilatory effort in patients with respiratory failure. We present preliminary results of an ongoing study. PATIENTS AND METHODS: In 5 patients with respiratory failure due to different underlying disorders (pulmonary fibrosis, bilateral diaphragm paralysis, COPD) we compared the transdiaphragmal pressure-time integral. PTdi (integral off Pdi dt) after 15 minutes of noninvasive PAV to the baseline values without ventilatory support. RESULTS AND CONCLUSION: Four patients showed reduction of PTdi to various extend. One patient who presented low diaphragmal activity at baseline due to diaphragmal paralysis showed a slight increase in PTdi during ventilation. Mean PTdi decreased by 26.7%. PaCO2 in the 5 patients showed no significant change after 15 minutes of ventilation, thus indicating that with noninvasive PAV patients can maintain constant ventilation with reduced effort.
Aged↗
[Long-term signal processing and time series analysis in internal medicine].
Explore the source record for details and available documents.
Humans↗
[Strategies for long-term registration of physiologic parameters in internal medicine].
Explore the source record for details and available documents.
Blood Pressure Monitors↗
Surgical maxillofacial treatment of obstructive sleep apnea.
Obstructive sleep apnea is the most common sleep-related breathing disorder, with a surprisingly high prevalence. The treatment of choice is nasal continuous positive airway pressure (CPAP) ventilation during sleep, which has to be applied throughout the patient's whole life. Because of various underlying pathomechanisms in patients with certain craniofacial disorders--narrow posterior airway space and maxillary-mandibular deficiency--surgical therapy by craniofacial osteotomies seems possible. A series of 38 consecutive patients were treated by 10-mm maxillomandibular advancement by retromolar sagittal split osteotomy and Le Fort I osteotomy, respectively. Obstructive sleep apnea syndrome was improved considerably in all patients; there was no significant difference compared to the results under nasal CPAP. In 37 of 38 patients, the postoperative apnea-hypopnea index was reduced clearly to under 10 per hour, oxygen saturation rose, and sleep quality improved. This was achieved by maxillomandibular advancement of 10 mm without secondary refinements in all but 2 patients. In one patient, the apnea-hypopnea index could only be reduced to 20 per hour, probably because of insufficient maxillary advancement. These results indicate that successful surgical treatment is possible in a high percentage of selected patients with certain craniofacial characteristics. In addition to cardiorespiratory polysomnography, there should be routine cephalometric evaluation of all patients. Maxillomandibular advancement should be offered as an alternative therapy to all patients with maxillary and/or mandibular deficiency or dolichofacial type in combination with narrow posterior airway space.
Adult↗
Long-term follow-up after surgical treatment of obstructive sleep apnoea by maxillomandibular advancement.
Obstructive sleep apnoea (OSA) is a common disorder with potentially serious consequences. If maxillary and mandibular deficiency, often in combination with a narrow posterior airway space is present, therapy of OSA by maxillomandibular osteotomy is possible. However, long-term follow-up of patients undergoing these procedures is lacking. We present the results of 15 OSA patients (1 female and 14 males), who underwent maxillomandibular advancement surgery with a follow-up of at least 2 yrs. Polysomnography was performed before surgery, after 6-12 weeks, and 1 and 2 yrs postoperatively. Mean apnoea/hypopnoea index (AHI) decreased from 51.4 events.h-1 before therapy to 5.0 events.h-1 6 weeks postoperatively, and was 8.5 events.h-1 after 2 yrs. Oxygen saturation significantly increased following surgery. After 2 yrs, the AHI was < 10 events.h-1 in 12 out of 15 subjects. No significant changes were found comparing the 6-12 weeks versus the 2 year follow-up data. The significant increase in stage 3/4 non-rapid eye movement (NREM) sleep and decrease in stage 1 NREM sleep, indicative of the restoration of normal physiological sleep structure, persisted in 14 of the 15 subjects 2 yrs postoperatively. Three patients, however, did not show satisfactory improvement 2 yrs postoperatively; two showed obstructive and one central respiratory events. This study demonstrates that maxillomandibular advancement is successful in a high percentage of patients carefully selected by cephalometric and polysomnographic investigation. Postoperative success has proved to be stable over a period of 2 yrs. Further preoperative evaluation seems necessary in patients with predominantly mixed or central apnoeas.
Adult↗
Influence of noninvasive positive pressure ventilation on inspiratory muscle activity in obese subjects.
Noninvasive positive pressure ventilation (NPPV) can improve ventilation in obese subjects during the postoperative period after abdominal surgery. Compared to nasal continuous positive airway pressure (nCPAP), NPPV was superior in correcting blood gas abnormalities both during the night-time and during the daytime in a subgroup of patients with the obesity hypoventilation syndrome (OHS). However, as it is unknown, if and to what extent NPPV can unload the respiratory muscles in the face of the increased impedance of the respiratory system in obesity, this is what was investigated. Eighteen obese subjects with a body mass index > or = 40 kg x m(-2) were investigated during the daytime, which included five healthy controls (simple obesity (SO)), seven patients with obstructive sleep apnoea (OSA) and six patients with the obesity hypoventilation syndrome (OHS). Assisted PPV was performed with bi-level positive airway pressure (BiPAP), applied via a face mask. Inspiratory positive airway pressure (IPAP) was set to 1.2 or 1.6 kPa and expiratory positive airway pressure (EPAP) was set to 0.5 kPa. Inspiratory muscle activity was measured as diaphragmatic pressure time product (PTPdi). Comparison of spontaneous breathing with BiPAP ventilation showed no significant difference in breathing pattern, although there was a tendency towards an increase in tidal volume (VT) in all three groups and a decrease in respiratory frequency (fR) in patients with OSA and OHS. End-tidal carbon dioxide (PET,CO2) with BiPAP was unchanged in SO and OSA, but was decreased in OHS. In contrast, inspiratory muscle activity was reduced by at least 40% in each group. This was indicated by a decrease in PTPdi with BiPAP 1.2/0.5 kPa from mean+/-SD 39+/-5 to 20+/-9 kPa x s (p<0.05) in SO, from 42+/-7 to 21+/-8 kPa x s (p<0.05) in OSA, and from 64+/-20 to 38+/-17 kPa x s (p<0.05) in OHS. With BiPAP 1.6/0.5 kPa, PTPdi was further reduced to 17+/-6 kPa x s in SO, and to 17+/-6 kPa x s in OSA, but not in OHS (40+/-22 kPa x s). We conclude that noninvasive assisted ventilation unloads the inspiratory muscles in patients with gross obesity.
Adult↗
Sleep-related myocardial ischemia and sleep structure in patients with obstructive sleep apnea and coronary heart disease.
STUDY OBJECTIVES: Patients with coronary heart disease (CHD) and obstructive sleep apnea may have an increased cardiac risk due to nocturnal myocardial ischemia triggered by apnea-associated oxygen desaturation. Sleep structure in patients with obstructive sleep apnea is fragmented by activation of the central nervous system (CNS) (arousal) due to obstructive apneas. Nocturnal myocardial ischemia may lead to activation of the CNS as well. PATIENTS: Fourteen patients with obstructive sleep apnea and CHD disease and seven patients suffering from obstructive sleep apnea without CHD were studied. Overnight sleep studies and simultaneous six-lead ECG recordings were performed. In addition, sleep studies and ECG recordings were performed with administration of a sustained-release nitrate in these patients in a double-blinded crossover design. RESULTS: Analysis of three nights' recordings revealed 144 episodes of nocturnal myocardial ischemia in six subjects. Five patients had underlying CHD and one patient exhibited diffuse wall defects of the coronary arteries; also, 85.4% of ischemic episodes were concomitant with apneas and oxygen desaturation > 3%, and 77.8% of ischemic episodes occurred during rapid eye movement (REM) sleep, although total amount of REM sleep was only 18% of total sleep time. Mean oxygen saturation was significantly lower (p < 0.05) during apnea-associated ischemic episodes than during nonapnea-associated ischemia (77.3% vs 93.1%). Nitrate administration did not reduce ischemic episodes. Sleep architecture (macrostructure) exhibited a reduction in sleep stages non-REM 3 and 4 and REM sleep. Comparing the microstructure of sleep (arousals) within episodes with and without ischemia but similar criteria like sleep stage, apnea activity, and oxygen saturation, we found significantly more (p < 0.01) and severe (p < 0.001) arousals during periods with myocardial ischemia than during control episodes. In addition, microstructure of sleep was disturbed by myocardial ischemia itself in absence of apneas. CONCLUSION: It is concluded that patients with CHD and obstructive sleep apnea are endangered by apnea-associated ischemia and that these ischemic episodes lead to activation of the CNS and additional fragmentation of sleep. Patients with nocturnal ischemia should be screened for underlying sleep apnea even if nitrate therapy fails.
Aged↗
Effect of angiotensin converting enzyme inhibition [Cilazapril] on blood pressure recording in hypertensive obstructive sleep apneic patients.
We investigated the efficacy of an Angiotensin Converting Enzyme [ACE] inhibitor on daytime and night-time blood pressure in 55 male hypertensive patients with moderately severe to severe obstructive sleep apnea. We resolved to determine if treatment oriented towards the reduction of hypertension would be successful, despite persistent repetitive hypoxemia and sleep-disordered breathing. The study was a randomized, double-blind, single daily dose, placebo-controlled protocol, with 8 days drug intake (placebo or 2.5 mg Cilazapril) and monitoring on the final day of drug administration. Subjects underwent continuous 24-h arterial blood pressure monitoring during baseline and treatment conditions. Polysomnography was performed at night during the 24-h arterial monitoring period. Cilazapril (2.5 mg) lowered systolic, diastolic and mean blood pressure, despite persistence of repetitive obstructive apneas during sleep and the associated repetitive hypoxemia. The lowering of blood pressure occurred without a significant change in heart rate, and was noted during nocturnal sleep, performance testing and graded exercise.
Adult↗
[Respiratory function diagnosis during sleep: possibilities and limitations].
Diagnosis of the respiratory function during sleep is based on a continuous recording of all necessary signals. These are basically respiratory flow, respiratory effort and blood gases. In addition, sleep stages, body position and cardiovascular function have to be monitored to distinguish the different forms of sleep related breathing disorders as there are obstructive, mixed and central apnea and hypoventilation. The main evaluation is a simple counting of events and the calculation of an index related to total sleep time. These indices are of limited value because all information about the duration of the events is lost and about the severity which depends on the actual blood gas values. A computer assisted evaluation of respiration can overcome these limitations and allows to evaluate sleep stage dependencies in addition. Based on the duration of respiratory events only it was possible to distinguish patient groups which also provided different blood gas values at daytime. Determination of the critical closing pressure of the upper airways during sleep can help to quantify effects of body weight loss and other therapeutic interventions beside ventilation therapy in patients with sleep related breathing disorders. Quantitative characterisation of respiration during sleep is limited by the fact that most methods available induce changes in sleep or respiration itself. A study on healthy subjects proved an increased number of arousals during cardiorespiratory polysomnography. Therefore the added value obtained by quantitative methodology (pneumotachograph and esophageal pressure) must be weighted against non-invasive technology (inductive plethysmography). Non-invasive methods can provide comprehensive information about the respiratory function, especially if extensive computer-assisted evaluation is used. These evaluations still need further improvements. Nevertheless they can help to clarify the different types of respiratory regulation present in NREM-, REM-sleep and awake state.
Carbon Dioxide↗
[Actigraphy: methodological limits for evaluation of sleep stages and sleep structure of healthy probands].
UNLABELLED: Purpose of the investigation was to evaluate the differences of movement density during the sleep stages and waking. 22 diurnally active, healthy, male volunteers of mean age 30.7 (+/-Standard deviation +/- 3.3) years and a Body-Mass-Index 23.6 +/- 3.3 kg/m2 participated in the study. All subjects were recorded in the sleep lab via cardiorespiratory polysomnography and wrist actigraphy (Ambulatory Monitoring, Ardsley, USA) worn on the non-dominant hand, for two consecutive nights. The activity data, consisting of the number of zero crossings (NZC) were recorded in 1-minute periods. Sleep stages were scored visually according to standard criteria. EEG- and actigraphy data were converted to the same data format (European Feature Files). Attaching the actimetry data to the sleep stages was calculated mean NZC for every sleep stage and Wake. In spite of high differences in total individual NZC we observed that most NZC occurred during Wake. NREM 1 movement density was significantly higher in 19 recordings (86%) than in any other sleep stage. In 18 cases (82%) lowest movement density was found in NREM 3/4 with significant difference to all other sleep stages. Within 50% of the recordings were found decreasing activity in the following sequence of stages: Wake > NREM 1 > REM > NREM 2 > NREM 3/4 However, in all other cases there was a varying pattern of activity. CONCLUSION: Although there is some correlation between motor activity and sleep stages, the predictive value of actimetry data analysis in the assessment of sleep structure appeared to be limited mainly by individual movement density, especially during REM and NREM 2.
Adult↗
[Carotid baroreflex in sleep apnea patients].
15 patients (11 male, 9 female) with obstructive sleep apnoea syndrome (OSAS) and 10 healthy age- and weight-matched control subjects volunteered to participate in the study to test circadian variations of cardiac response to activation of carotid baroreceptors. Activation of carotid baroreceptors was evoked by applying a negative pressure to both left and right carotid sinus regions, using two small separate neck-suction capsules. All experiments were performed under standard conditions every two hours. The cardiac response to carotid baroreceptors activation was significantly reduced in OSAS Patients, to a greater degree in the group of hypertensive patients. A characteristic circadian rhythm of baroreceptor reactivity persisted in all OSAS patients. Thus, OSAS patients constitute a high-risk group for the development of cardiovascular diseases and pathological course of blood pressure during daytime.
Blood Pressure↗
[Use of discontinuous long-term blood pressure measurement (Spacelabs 90207) in patients with sleep apnea--a comparison with intra-arterial data].
Circadian blood pressure (BP) profile is an important determinant of cardiovascular risk. Patients with Sleep-Related Breathing Disorders (SRBD) often suffer from arterial hypertension and an altered circadian blood pressure profile. The aim of this study was to compare intraarterial blood pressure recordings with DBPR (Discontinuous Blood Pressure Recorder using Spacelabs 90207) in 20 patients with mild to moderate arterial hypertension and mild to moderate SRBD. Our results of overnight measurements show that the mean arterial pressure seems to be the most reliable value (mean difference Spacelabs-Part: +1.7 mmHg). In contrast, the systolic BP was systematically underestimated (mean: -17.5 mmHg) while the diastolic value was systematically overestimated (mean: +9.3 mmHg) by Spacelabs. Our data show that neither systolic nor diastolic BP from the Spacelabs measurement reflected the real cardiovascular load. Since the mean arterial pressure proved to be the most reliable value, this value should be used to distinguish between dipper and non-dipper in circadian BP profiles. Further, reliable noninvasive continuous measurement of the BP is required to assess the real vascular load in patients with SRBD during the night.
Adult↗
[Increased daytime tiredness, nocturnal hypertension and sleep apnea: studies in rural general practice].
Studies in a Rural General Practice: Sleep-Related Breathing Disorders (SRBD) and altered circadian blood pressure profile are related to increased cardiovascular risk. We investigated the prevalence and coincidence of both diseases in male patients from a general practice in a small community of 2500 people. Out of 409 selected patients (using a questionnaire regarding symptoms and findings of SRBD), 185 were monitored in an outpatient setting with an apnoea-screening system Mesam IV. Ambulatory blood pressure monitoring (Spacelabs 90207). Holter-ECG and actigraphy were also measured. Sixty patients had a Respiratory Disturbance Index (RDI) > 10. An indication for further sleep studies was seen in 40 patients; 36.5% of daytime hypertensives were "Non-Dipper", and 47.6% of normotensives were also "Non-Dipper". Excessive daytime sleepiness (EDS) is an important symptom of SRBD, and in this investigation we noticed a large number of patients without this symptom suffering from relevant SRBD. Therefore, absence of EDS alone is not indicative for the use of ambulatory monitoring.
Adult↗