Perspectives on improving blood pressure control to reduce the clinical and economic burden of hypertension

The clinical and economic burden of hypertension is high and continues to increase globally. Uncontrolled hypertension has severe but avoidable long-term consequences, including cardiovascular diseases, which are among the most burdensome and most preventable conditions in Europe. Yet, despite clear guidelines on screening, diagnosis and management of hypertension, a large proportion of patients remain undiagnosed or undertreated. Low adherence and persistence are common, exacerbating the issue of poor blood pressure (BP) control. Although current guidelines provide clear direction, implementation is hampered by barriers at the patient-, physician- and healthcare system levels. Underestimation of the impact of uncontrolled hypertension and limited health literacy lead to low adherence and persistence among patients, treatment inertia among physicians and a lack of decisive healthcare system action. Many options to improve BP control are available or under investigation. Patients would benefit from targeted health education, improved BP measurement, individualized treatment or simplified treatment regimens through single-pill combinations. For physicians, increasing awareness of the burden of hypertension, as well as offering training on monitoring and optimal management and provision of the necessary time to collaboratively engage with patients would be useful. Healthcare systems should establish nationwide strategies for hypertension screening and management. Furthermore, there is an unmet need to implement more comprehensive BP measurements to optimize management. In conclusion, an integrative, patient-focused, multimodal multidisciplinary approach to the management of hypertension by clinicians, payers and policymakers, involving patients, is required to achieve long-term improvements in population health and cost-efficiency for healthcare systems.

[Abdominal pain and signs of acute pancreatitis in a 60-year-old man]

Spontaneous splenic rupture is an uncommon complication of acute pancreatitis. This report describes the case of a 60-year-old man with acute pancreatitis complicated by splenic rupture. The patient was admitted to the emergency department with pain in the upper abdomen that had been present for 2 days. He was diagnosed with acute pancreatitis of alcoholic etiology. The patient was admitted to the hospital for two recurrent episodes in the last 4 months of acute pancreatitis of alcoholic etiology. Magnetic resonance imaging of the abdomen revealed a suspicious area of necrosis. Seventy-two hours after admission, the patient had significant improvement in symptoms and the inflammation markers rapidly decreased. However, he showed clinical worsening on the seventh day of hospitalization, with increasing abdominal distension and reduced hemoglobin levels. A CT angiography showed a large amount of free fluid in the abdominal cavity, along with a large splenic hematoma. The patient subsequently underwent laparotomy, which showed hemoperitoneum due to rupture of the splenic parenchyma. A splenectomy was performed with resection of the pancreatic tail.

[Guidelines in Practice: The New S3 Guideline "Sleeping Disorders - Sleep-Related Abnormal Breathing"]

Sleep related breathing disorders include central sleep apnea (CSA), obstructive sleep apnea (OSA), sleep-related hypoventilation, and sleep-related hypoxia. These disorders are frequent and growing in clinical relevance. The related chapter of the S3 guideline "Non-restorative sleep/Sleep disorders", published by the German Sleep Society (DGSM), has recently been updated in November 2016. Epidemiology, diagnostics, therapeutic procedures, and classification of sleep related disorders have been revised. Concerning epidemiology, a considerably higher mortality rate among pregnant women with OSA has been emphasized. With regards to diagnostics, the authors point out that respiratory polygraphy may be sufficient in diagnosing OSA, if a typical clinical condition is given. For CSA, recommendations were changed to diagnose CSA with low apnea rates present. Significant changes for treating CSA in patients with left ventricular dysfunction have been introduced. In addition, there is now to be differentiated between sleep-related hypoventilation and sleep-related hypoxaemia. Obesity hypoventilation syndrome is discussed in more detail. This article sums up and comments on the published changes.

Non-CPAP therapies in obstructive sleep apnoea

In view of the high prevalence and the relevant impairment of patients with obstructive sleep apnoea syndrome (OSAS) lots of methods are offered which promise definitive cures for or relevant improvement of OSAS. This report summarises the efficacy of alternative treatment options in OSAS. An interdisciplinary European Respiratory Society task force evaluated the scientific literature according to the standards of evidence-based medicine. Evidence supports the use of mandibular advancement devices in mild to moderate OSAS. Maxillomandibular osteotomy seems to be as efficient as continuous positive airway pressure (CPAP) in patients who refuse conservative treatment. Distraction osteogenesis is usefully applied in congenital micrognathia or midface hypoplasia. There is a trend towards improvment after weight reduction. Positional therapy is clearly inferior to CPAP and long-term compliance is poor. Drugs, nasal dilators and apnoea triggered muscle stimulation cannot be recommended as effective treatments of OSAS at the moment. Nasal surgery, radiofrequency tonsil reduction, tongue base surgery, uvulopalatal flap, laser midline glossectomy, tongue suspension and genioglossus advancement cannot be recommended as single interventions. Uvulopalatopharyngoplasty, pillar implants and hyoid suspension should only be considered in selected patients and potential benefits should be weighed against the risk of long-term side-effects. Multilevel surgery is only a salvage procedure for OSA patients.

Influence of tissue affinity of angiotensin-converting enzyme inhibitors on left ventricular remodeling after myocardial infarction

BACKGROUND

The demonstration of local renin-angiotension systems has raised the question of whether angiotensin-converting enzyme (ACE) inhibitors with different tissue affinities differ with regard to their effects on postinfarction remodeling.

HYPOTHESIS

The study was undertaken to investigate the influence of ACE inhibitors with different tissue affinity on morphology and function of the infarcted left ventricle.

METHODS

In all, 52 patients (17 women, 35 men, 38-73 years) with large acute myocardial infarction were randomized to receive either 25-75 mg/day captopril or 10-20 mg/day fosinopril beginning on the Day 7 after infarction. Of these, 28 had anterior and 24 had posterior wall infarctions. Infarct size was determined by the creatine kinase integral method. Fifty patients were examined by cinemagnetic resonance imaging (CMRI) 1 and 26 weeks after infarction. The following parameters were determined: left ventricular end-diastolic and end-systolic volume index (LVEDVI, LVESVI), ejection fraction (LVEF), infarct weight, and muscle mass (LVMM). The volume-to-mass ratio (VMR) was calculated and the clinical status according to the guidelines of the New York Heart Association (NYHA) was documented at each examination time. The results were compared with those of a historical sample without ACE-inhibitor therapy examined in an identical manner (n = 31, 10 women, 21 men, 36-75 years).

RESULTS

LVEDVI and LVESVI increased in the first 6 months after infarction by 24.9 and 36.6%, respectively, in the historical sample; by 11.0 and 7.8%, respectively, under captopril; and by 13.1 and 10.7%, respectively, under fosinopril. LVEF decreased by 14.9% in the untreated sample, by 3.7% under captopril and by 5.0% under fosinopril. Infarct weight and LVMM increased by 12.7 and 15.3%, respectively, without ACE inhibition, by 5.7 and 10.1%, respectively, in patients treated with captopril, and by 6.1 and 9.3%, respectively, in patients treated with fosinopril. The VMR increased by 7.4% in the historical sample, by 3.5% in the captopril group, and by 1.8% in the fosinopril group. The NYHA clinical status improved by 18.2% without ACE inhibition, by 42.9% in the captopril group, and by 26.3% in the fosinopril group. The differences between the two ACE-inhibitor groups and the reference group were all significant, while the differences between the captopril group and the fosinopril group were significant only for VMR (p < 0.01) and NYHA class (p < 0.05).

CONCLUSIONS

Both captopril and fosinopril have a comparable positive influence on postinfarction remodeling and on clinical status. Lipophilicity and tissue affinity do not seem to play a clinically important role in ACE-inhibitor therapy after infarction.

[Are there alternative therapeutical options other than CPAP in the treatment of the obstructive sleep apnea syndrome]

Many patients with the obstructive sleep apnea syndrome (OSAS) look for alternative conservative or surgical therapies to avoid to be treated with continuous positive airway pressure. In view of the high prevalence and the relevant impairment of the patients lots of methods are offered which promise definitive cure or relevant improvement of OSAS. The working group "Apnea" in the German Society of Sleep Medicine and Research established a task force to evaluate the scientific literature on non-CPAP therapies in the treatment of OSAS according to the standards of evidence-based medicine. This paper summarizes the results of the task force. The data were unsatisfactorily for most of the methods. Sufficient data were available for intraoral appliances (IOA) and the maxillomandibular osteotomy (MMO). IOA's can reduce mild to moderate respiratory disturbances, MMO are efficient in the short and long term but are performed only in special situations such as craniofacial dysmorphias. Weight reduction and body positioning cannot be recommended as a single treatment of OSAS. Most surgical procedures still lack sufficient data according to the criteria of evidence based medicine. Resections of muscular tissue within the soft palate have to be strictly avoided. But even success following gentle soft palate procedures is difficult to predict and often decreases after years. Results in other anatomical regions seem to be more stable over time. Today combined surgeries in the sense of multi-level surgery concepts are of increasing interest in the secondary treatment after failure of nasal ventilation therapy although more data from prospective controlled studies are needed. There is no evidence for any other treatment options.

A test for the determination of sustained attention in patients with obstructive sleep apnea syndrome

BACKGROUND AND OBJECTIVES

To investigate the parameter daytime sleepiness in patients with the sleep apnea syndrome (SAS), a test for measurement of sustained attention was developed. The present studies were performed on volunteers undergoing preemployment medical examinations and SAS patients to determine the extent to which test results are in agreement with the symptoms of SAS and traffic accident reports, and also with daytime sleepiness, and whether learning or therapeutic effects can be seen with repeated tests prior to and following treatment with nasal continuous positive airway pressure (nCPAP).

METHODS

PARTICIPANTS

125 healthy volunteers, and two groups of 28 SAS patients each.

DESIGN

Study A: The volunteers underwent a single attention test and completed a questionnaire concerned with traffic accidents and symptoms of sleep-related breathing disorders. Study B: SAS patients underwent two attention tests before treatment. Study C: SAS patients underwent one attention test before and one after nCPAP therapy.

RESULTS

Study A: The error rate in volunteers without symptoms of sleep-related breathing disorders (51 persons) was 4.7 +/- 4.3% (number of errors 14.1 +/- 12.9), 95% CI: 1.2 (number of errors 3.6). No dependence of the error rate on age, BMI or sex was found. In persons with a history of apneic events (n = 10), the error rate was 10.6 +/- 10.0% (number of errors 31.8 +/- 30), in those with more than two accidents during the last 5 years (n = 4), it was increased to 15.3 +/- 9.7% (number of errors 45.9 +/- 29.1). Study B: Among SAS patients, no significant learning effect was seen, and prolongation of the test duration beyond 30 min had no effect on the test results. Study C: The error rate improved significantly with nCPAP [10.6 +/- 13.5 vs. 6.4 +/- 8.9% (number of errors 31.8 +/- 40. 5 vs. 19.2 +/- 26.7), p < 0.001].

CONCLUSIONS

The attention test can be helpful for the measurement of daytime sleepiness, and CPAP therapy can improve test performance.

Prospective randomized comparison of impedance-controlled auto-continuous positive airway pressure (APAP(FOT)) with constant CPAP

Background: The measurement of impedance permits reliable detection of obstructive apneas, hypopneas and upper airways resistance syndrome.Objective: To establish whether impedance-controlled self-adjusting positive airway pressure therapy (APAP(FOT)) is equally as good as constant continuous positive airway pressure (CPAP) in the treatment of sleep apnea syndrome (OSAS).Methods: Twenty men and five women with OSAS (age 52.8+/-9.0 years, body mass index (BMI) 31.4+/-5.0 kg/m(2), AHI 32.2+/-18.1/h (mean+/-SD)) underwent baseline polysomnography, manual CPAP titration and two nights of treatment, one with APAP(FOT), one with constant CPAP.Results: With both modes, a significant reduction in respiratory disturbances was seen (apnea/hypopnea index (AHI) baseline 32.2+/-18.1/h, constant CPAP 6.6+/-8.7, APAP(FOT) 5.5+/-3.8/h, P<0.001 baseline vs. each treatment mode). Under APAP(FOT), the sleep profile was normalized (S3/4 baseline 16.3+/-13.9% total sleep time (TST), APAP(FOT) 21.6+/-10.9% TST, P<0.05, rapid eye movement (REM) 14.2+/-6.7% TST vs. 20.3+/-7.3% TST, P<0.01), while with constant CPAP, a tendency towards improvement was found. The mean treatment pressure with APAP(FOT) was significantly lower than the constant CPAP (5.7+/-2.1 vs. 8.3+/-1.6 mbar, P<0.001).Conclusion: We conclude that APAP(FOT) is at least as effective as constant CPAP in normalizing sleep and breathing in OSAS.

Self-adjusting continuous positive airway pressure therapy based on the measurement of impedance. A comparison of free pressure variation and individually fixed higher minimum pressure

BACKGROUND

Measurement of impedance using forced oscillation technique is a sensitive means of detecting airway obstructions, including the obstructive sleep apnea syndrome (OSAS).

OBJECTIVE

The present study was conducted to determine whether treatment with an automated impedance-controlled continuous positive airway pressure (CPAP) device (APAP(FOT)) is possible in patients with OSAS, and which is the best range of pressure variation in automatical CPAP treatment. We investigated two modes of APAP(FOT) with different pressure ranges: (1) the widest technically possible pressure range and (2) a range with individually defined minimum pressure.

METHODS

Ten patients [9 men, age 56.6+/-10.5 years, BMI 32.0+/-4.5 kg/m(2), apnea/hypopnea index (AHI) 18.2+/-13.3 /h] had a diagnostic polysomnography (baseline). After manual titration of positive airway pressure they were submitted, in randomized order, to two modes of the APAP(FOT) device, namely pressure range of 4.0- 15.5 mbar (mode 1 free range) and an individually fixed higher minimum pressure with a maximum pressure of 15.5 mbar (mode 2).

RESULTS

While the manually titrated pressure was 8.0+/-1.3 mbar, in mode 1 it was 5.6+/-2.1 mbar (p<0.01); in mode 2 7.3+/-1.6 mbar (p< 0.05). Both of these modes suppressed abnormal respiratory events (baseline AHI 18.2+/-13.3/h; mode 1: 2.5+/-1.9; mode 2: 1.8 +/-0.7, p<0.01 in each case), and increased slow wave sleep (baseline: 10.6+/-8.0%, mode 1: 20.2+/-10.4%, p<0.05; mode 2: 22.3+/-9.3%, p<0.01). In mode 1, the pressure was lower than that titrated manually in 73.2% of total sleep time, in mode 2 in 48.6%, while pressures higher than those derived manually were observed in 13.0% in mode 1 and in 19.1% in mode 2.

CONCLUSIONS

The data indicate that impedance-controlled CPAP (APAP(FOT)) allows adequate treatment of OSAS patients at significantly lower pressures as compared with manually titrated pressure. Differences between the two modes are only minor.

Better visualization of transbronchial biopsy using CT fluoroscopy

PURPOSE

Computed tomography fluoroscopy (CTF) provides the capability for continuous CT imaging and has been increasingly used in interventional procedures. Our objective was to assess the usefulness of CTF in the monitoring of transbronchial biopsy procedures.

METHODS

We evaluated nine patients in whom yield of "conventional" transbronchial biopsies had failed. CTF was performed on a Somatom Plus 4 Power scanner (CARE Vision CT, Siemens, Forchheim, Germany) using 120 kV, 50 mA at a frame rate of eight images per second on a matrix of 256 x 256. Image reconstruction was based on a partial scan with an acquisition time of 0.5 sec. The maximal time without interruption was 79 sec; after stopping for a few seconds a new period of 79 sec was available. The number of biopsies, procedure times, applied dose, and histologic results were documented.

RESULTS

With CTF-guided transbronchial biopsy, the yield of the biopsies was improved. In seven patients biopsy yielded bronchial cancer; in one patient histopathologic examination showed tuberculosis. Only in one patient did CTF-guided transbronchial biopsy fail. The mean number of biopsies was four in each patient. Mean fluoroscopy time was 165 +/- 92 sec (range 111-272 sec) and mean procedure time was 800 +/- 302 sec (range 480-1081 sec). The applied dose ranged between 500 and 1224 mSv; the mean applied dose was 743 +/- 414 mSv. There were no fatal complications.

CONCLUSION

Computed tomography fluoroscopy appears to facilitate visualization of transbronchial biopsy procedures, with the drawback of increased radiation exposure. To compare the "conventional" method versus CTF a randomized prospective study is necessary.

Self-adjusting nasal continuous positive airway pressure therapy based on measurement of impedance: A comparison of two different maximum pressure levels

STUDY OBJECTIVE

Automatic titration using the forced oscillation technique (FOT) has recently been developed for the treatment of obstructive sleep apnea syndrome (OSAS). So far, it is not known if therapy with automatic nasal continuous positive airway pressure (nCPAP) using a preset upper pressure limitation or a free range (which might lead to higher mean pressure) is preferable with regard to obstructive events, sleep stages, and pressure characteristics.

DESIGN

After diagnostic polysomnography, patients were randomly assigned to two settings with the self-adjusting nCPAP (APAP) device based on the FOT. In mode 1, the pressure variation ranged from 4 to 15.5 cm H(2)O, and in mode 2, the pressure variation ranged from 4 cm H(2)O to an individual upper pressure limit.

PATIENTS

Eleven men, aged 53.0 +/- 6.8 years with a body mass index of 32.4 +/- 5.1 kg/m(2) and an apnea-hypopnea index (AHI) of 31.6 +/- 26.6/h.

MEASUREMENTS AND RESULTS

Manually titrated pressure was at 9.3 +/- 2.1 cm H(2)O, the mean pressure in mode 1 was 5.4 +/- 1.0 cm H(2)O (p < 0.01), and the mean pressure in mode 2 was 5.1 +/- 0.7 cm H(2)O (p < 0.01). A reduction of respiratory events (baseline AHI, 31.6 +/- 26.6/h; AHI in mode 1, 3.4 +/- 4.5; AHI in mode 2, 5.0 +/- 7.2; each with p < 0.001) and an increase in the "rapid eye movement" stage of sleep (baseline, 13.0 +/- 5.5%; mode 1, 22.0 +/- 7.7 [p < 0. 05]; mode 2, 23.0 +/- 7.9 [p < 0.01]) were achieved. In mode 1, the mean pressure was below the manual pressure 91.7 +/- 9.3% of the time, and in mode 2, the mean pressure was below the manual pressure 90.4 +/- 6.3% of the time. The manual pressure was exceeded by 5.5 +/- 7.4% (mode 1) and by 5.2 +/- 3.1% (mode 2).

CONCLUSION

We conclude that nCPAP therapy based on the FOT permits the adequate treatment of OSAS with significantly lower pressure than manually titrated nCPAP therapy does. A presetting of an upper pressure limit has no advantage compared to free range.

Multiple myeloma involving the stomach with vitamin B12 deficiency

Involvement of the gastrointestinal tract by plasmocytoma is rare. In a 78-year-old man with IgA lambda multiple myeloma stage IIIB, the evaluation of a megaloblastic anaemia revealed a subnormal vitamin B12 level. Urinary excretion of isotope-labelled vitamin B12 was reduced. Tests for gastric parietal cell and intrinsic factor antibodies were negative. There were no clinical signs of an insufficient absorption in the ileum. Biopsy specimens of the stomach showed a dense, diffuse infiltrate of malignant plasma cells in the lamina propria of fundus and corpus. A urease test for Helicobacter pylori was positive. There was a minor haematological improvement when vitamin B12 was given parenterally. Several combinations of cytostatic drugs had no effect on the manifestations of the multiple myeloma. In our patient the vitamin B12 deficiency may be related to a displacement or destruction of parietal cells by malignant plasma cells.

[Obstructive sleep apnea and hypertension. Diagnostic procedure--exclusion of risk factors--nCPAP treatment]

Obstructive sleep apnea is a common illness with an estimated prevalence of 3% in the adult population. At least 50% of patients with obstructive sleep apnea also have hypertension, while approximately 30% of hypertensives also suffer from obstructive sleep apnea. This high level of coincidence together with the results of recent epidemiological studies and the frequent observation that hypertension may reverse under effective treatment for obstructive sleep apnea strongly suggest that this sleep disorder is an independent causal factor in the development of hypertension. The present paper considers the association of sleep apnea and hypertension and the resulting diagnostic and therapeutic consequences.

[Hereditary nonpolyposis colonic carcinoma with primary extra-colic manifestation]

A 62-year-old woman presented with nausea, weakness, and vasovagal attack. She had a history of a carcinoma of the endometrium 19 years prior to admission, and adenocarcinomas of the cecum, ascending colon, transverse colon, rectum and sigmoid during the subsequent years. Due to the typical history, including family history, hereditary nonpolyposis colorectal cancer (HNPCC) was diagnosed 6 months prior to admission. Physical examination was normal with the exception of pallor of the skin and the palpebral conjunctivas. Laboratory values showed hypochromic, microcytic anemia (hemoglobin: 6.5 g/dl; MCV 70.1 fl; MCH 22.8 micrograms). Esophagogastroduodenoscopy revealed an exophytic mass protruding into the lumen of the inferior part of the duodenum. Carcinoma of the duodenum as a manifestation of HNPCC was diagnosed and partial duodenectomy performed. Macroscopic and microscopic examination revealed two adenocarcinomas--next to one another--7.0 cm and 2.5 cm in diameter. HNPCC is often overlooked and its relevance underestimated. Since diagnosis of this disease has major implications, all patients with colorectal cancer, and also young women with carcinoma of the endometrium, should be screened for HNPCC.

[Pronounced hypersomnia in a 13-year-old patient with periodic leg movements]

We report on a rare case of a thirteen-year old female with excessive daytime somnolence, which was caused by periodic leg movement. This underlines the necessity first to consider this diagnosis and second to record unconditionally the EMG derivation at minimum of the tibialis muscles in all patients with hypersomnolence. Even if carbamazepine is not the treatment of choice, in this case it was of remarkable effect.

[Complications of nasal CPAP therapy. Consequences for general practice]

BACKGROUND

The prevalence of the obstructive sleep apnea syndrome is about 5% in the entire population. The amount of treatment-indications grows for this particular sleep-related breathing disorder due to the increasing usage of diagnostic screening tests. In most cases, the positive-pressure ventilation, PPV (nCPAP, nBiPAP) is considered as a highly effective form of treatment, in comparison to other treating methods. The residential polysomnographic supervised adjustment of the treatment is optimally applied to most of the patients. Due to the increasing number of the treated patients, the reports about the appearance of short-termed side effects during the adjustment of the PPV become more frequent.

PATIENTS AND RESULTS

We report on 9 patients who showed complications during the initial stage of treatment. The most common one, during the nCPAP-therapy, was the increase of central apneas. Because of this complication, a rapid optimization of the respiratory pressure or a change to a nBiPAP-therapy was necessary in 5 of the patients. 2 of the patients showed cardiac arrhythmias, some of which were severe. One patient produced a remarkable central hypoventilation during the initial phase of a nCPAP-therapy. The nBiPAP-titration combined with right-heart-catheter monitoring could demonstrate in another patient a possible cardiac decompensation through an increased ventilatory pressure.

CONCLUSION

The risk of a positive-pressure ventilation is higher in patients with accompanying cardiac, pulmonary, neuropsychiatric and/or otorhinolaryngologic disorders. Considering the various predisposing factors of the patients we suggest an intensive apparative monitoring as well as stuff-supervision during the introduction to a respiratory treatment. If complications appear, a rapid improvement of the ventilatory pressure or a change to another respiratory treatment is indicated.

[Coronary heart disease in patients with obstructive sleep apnea]

OBJECTIVE

As patients with severe obstructive sleep apnoea (OSA) have increased cardiovascular morbidity and mortality rates, the prevalence of coronary heart disease (CHD) was investigated in patients with OSA proven by polysomnography (apnoea/hypopnea index > or = 10/h).

PATIENTS AND METHODS

In 440 patients (400 men, 40 women; mean age 55.3 [16-80] years) with OSA proven by polysomnography, the possible diagnosis of CHD was assessed by history, physical examination, ECG at rest and on exercise, one- and two-dimensional echocardiography and, where indicated, myocardial scintigraphy and coronary angiography.

RESULTS

CHD was demonstrated by angiography in 24.6% (men: 26.4%; women: 7.5%). Adding patients with CHD diagnosed noninvasively, but unconfirmed by angiography, positive correlation was found in 33.2% (men: 34.8%; women: 17.5%).

CONCLUSION

There was a high prevalence of CHD in patients with OSA. This underlines the importance of careful cardiac diagnosis in patients with OSA.

[Obstructive sleep apnea in patients with coronary heart disease]

Patients with obstructive sleep apnea have an increased cardiovascular morbidity and mortality, those with co-existent coronary artery disease being particularly at risk. The object of our study was to evaluate the prevalence of obstructive sleep apnea in patients with coronary artery disease. 153 patients (117 men, 36 women) with verified coronary artery disease were given a highly sensitive standardized questionnaire. The 59 patients with pathological results were then checked with a 6-channel non-laboratory monitoring system. 22.2% of all patients had a respiratory disturbance index (RDI) above 5/h. and 14.4% above 10/h. 13.3% had a pathological RDI and additionally suffered from excessive daytime sleepiness. Patients with coronary artery disease have a high prevalence of obstructive sleep apnea and should consequently be screened for this sleep-related breathing disorder.

[Modification of cardiopulmonary performance parameters in patients with obstructive sleep apnea treated with nCPAP therapy]

nCPAP influences cardiopulmonary hemodynamic function in patients with obstructive sleep apnea (OSA). It is known that systolic function of the right and left ventricle, systemic and pulmonary hypertension, arterial blood gases and lung function during the day may improve under this treatment. We prospectively followed 30 patients with severe OSA and determined diastolic left ventricular function (Doppler echocardiography), cardiovascular efficiency (steady state exercise stress testing); and individual assessment of performance (standardized psychometric questionnaire) before, and 2 weeks and 6 months after initiation of nCPAP treatment. The following results could be obtained (first value after 2 weeks, second value after 6 months): Doppler echocardiography: E/A rose by 9.3% (p < 0.05) and another 0.5% (n.s.). E/A integral increased by 13.8% (p < 0.01) and another 3.5% (n.s.). Deceleration period decreased by 22.7% (p < 0.01) and another 3.1% (n.s.). Steady state exercise stress testing: Maximum performance rose by 10% (p < 0.05) and another 17.5% (p < 0.01). Heart rate ratio 100 W/rest dropped by 13.5% (p < 0.001) and another 6.5% (p < 0.01), systolic blood pressure ratio 100 W/rest by 0.8% (n.s.) and another 14.9% (p < 0.001). Diastolic blood pressure ratio 100 W/rest did not change significantly. Questionnaire: Assessment of well-being increased by 44.5% (p < 0.05) and another 16.9% (n.s.). After an initial drop of 0.8% (n.s.), quality of life increased by 14.9% (p < 0.05). Assessment of performance rose by 21.7% (p < 0.05) and another 4.1% (n.s.). nCPAP therapy in patients with OSA improves diastolic function of the left ventricle, cardiovascular performance and individual assessment of performance.

Magnetic resonance angiography as a technique for the visualization of hemodialysis shunts

In order to test the suitability of magnetic resonance angiography for the visualization of Brescia-Cimino hemodialysis shunts, 20 patients (8 women, 12 men, aged 24-69 years) were examined with this technique. The shunt arm was placed in an extremity coil. The time-of-flight method was applied. Examination time was less than 15 min. Arterial digital subtraction angiography (DSA) of the shunt arm was carried out additionally in 8 patients in whom pathological results had been obtained. Surgery was performed on 2 patients. In all cases, the feeding artery, anastomosis, and shunt were clearly visible. The results corresponded exactly to those of DSA and, in the patients who had undergone surgery, also to the situs. The patients stated that the examination technique was not very disturbing. Magnetic resonance angiography in the time-of-flight technique seems to be recommendable for the examination of Brescia-Cimino dialysis shunts. Compared to DSA, it has major advantages: it is noninvasive, and no ionizing radiation or contrast medium are associated with the procedure.

[Cine-MRT in the functional and morphological diagnosis of the heart after a myocardial infarct/ A comparison with angiocardiography, 2-dimensional echocardiography, intracardiac scintigraphy and enzymatic infarct size estimation]

PURPOSE

The aim of the study was to test the reliability of cine magnetic resonance imaging (cine-MRI) on the infarction heart with its altered geometry.

MATERIAL AND METHODS

61 patients (17 women, 44 men, 36-83 years, 32 with anterior, 29 with posterior wall infarction) received Cine-MRI in the true long and short axis of the heart and two-dimensional echocardiography one and 4 weeks post infarction. Two-level angiocardiography (ACG) and radionuclide ventriculography (RNV) were performed 4 weeks p.i. The size of myocardial infarction was determined enzymatically with the CK integral method. Left ventricular volume indices (EDVI, ESVI, SVI), ejection fraction (EF) and infarction weight (IW) were compared.

RESULTS

Excellent correlations existed between cine-MRI in the long and short axis for the volume indices and EF. Between cine-MRI in the short axis and ACG all correlations were excellent as well. They were significantly less satisfactory between cine-MRI and 2DE due to the inhomogeneity of echo quality. Cine-MRI and RNV produced similar EF results (r = 0.884), and a comparison of IW in cine-MRI and CK integral method also showed a good correspondence (r = 0.967).

CONCLUSION

Cine-MRI is a reliable method for the morphological and functional examination of post-myocardial infarction.

[Effects of nCPAP therapy on the blood picture in patients with obstructive sleep apnea]

In some patients with obstructive sleep apnea, changes in red blood cell count resembling polycythemia can be observed. If these changes result from the sleep-related breathing disorder, its adequate treatment should in turn induce a decrease of, for instance, hemoglobin concentration. We therefore set out by examining retrospectively the development of hemoglobin concentration under nCPAP in 130 patients with polysomnographically verified obstructive sleep apnea, comparing the values before treatment and after a mean of 12.0 months. During this period, hemoglobin mass concentration dropped from a mean of 153 +/- 13 g/Ls to 148 +/- 11 g/Ls (p < 0.001). Afterwards we prospectively examined in 50 patients the changes in complete blood cell count before and immediately after initiation of nCPAP treatment. It turned out that hemoglobin mass concentration dropped from a mean of 154 +/- 14 g/Ls to 148 +/- 14 g/Ls (p < 0.001), the erythrocyte count from 5.02 +/- 0.42/pl to 4.79 +/- 0.51/pl (p < 0.001), and hematocrit from 45.4 +/- 3.1% to 43.1 +/- 4.3% (p < 0.001) after only one night; no more significant change occurred after that. Increased hemoglobin mass concentrations, erythrocyte counts and hematocrit values can be the result of obstructive sleep apnea. Treatment of this sleep disorder with nCPAP will induce a quick and significant decrease of hemoglobin mass concentration, erythrocyte count, and hematocrit, independent of the initial values. This phenomenon points to the fact that changes in blood cell counts are not caused by a disturbance of erythropoesis but rather by alterations in volume regulation.

Clinical significance of ventricular late potentials in patients with obstructive sleep apnoea

Patients with obstructive sleep apnoea (OSA) have an increased cardiovascular mortality and probably also an increased incidence of sudden cardiac death. Thus the question arises whether ventricular late potentials can constitute markers for an increased electric vulnerability in these patients. Signal-averaged electrocardiograms were recorded in 64 patients (6 female, 58 male; mean age 53.2 y) with OSA (mean apnoea-hypopnoea index (AHI) 41.7 h-1 +/- 24.3 h-1). Furthermore, a continuous ambulatory electrocardiogram and gated radionuclide ventriculography were performed. Ventricular late potentials were recorded in 5 men out of 64 patients. Two of them had coronary artery disease (1 patient post-myocardial infarction), 2 hypertension, and 1 nocturnal hypertension. No correlation could be traced between left ventricular ejection fraction, severity and extent of ventricular premature beats, or severity of OSA and occurrence of ventricular late potentials. It was noticeable, however, that the patients with ventricular late potentials had severe OSA (mean AHI 50.2/h vs. 40.9/h). Although OSA may lead to structural myocardial changes that could be the basis for re-entrant circuits, ventricular late potentials were found in only 7.8% of these patients. The results of this study demonstrate that at present ventricular late potentials and signal-averaged electrocardiograms do not prove useful as screening methods for risk stratification of patients with OSA.

[Structural cardiac changes in patients with obstructive sleep apnea]

Important pathophysiological mechanisms in obstructive sleep apnea at night are increasing pleural pressure swings, hypoxia and hypercapnia, as well as central nervous arousals with consecutive fragmentation of regular sleep structure. They influence the cardiovascular system, at first only at night and at a later stage also during the day. This might result in cardiac structural changes: dilation and hypertrophy of the right ventricle, hypertrophy of the left ventricle, (especially of the muscular ventricular septum), dilation of right and left atrium. It is suggested that these cardiac structural changes are characteristic for obstructive sleep apnea and therefore define the "sleep apnea heart".

[Sleep disorders in patients with dialysis-dependent renal failure]

A questionnaire was performed in order to classify the prevalence of sleep disorders in patients with end-stage renal disease treated with hemodialysis. 69 patients (41 male, 28 female) with a median age of 57 years completed the questionnaire. 67% of these patients complained of sleep disorders. 31 patients (45%) had evidence of periodic leg movement syndrome, 22 patients (32%) of restless legs syndrome. 29 patients (42%) had difficulties in falling asleep, 27 patients (39%) in maintaining sleep and 17 (25%) experienced both. Snoring was found in 25 patients (36%), 13 patients (19%) seemed to have sleep apnea. These data show an increased prevalence of sleep disorders in patients with end-stage renal disease on hemodialysis treatment. We conclude that these patients should consequently be asked for sleep disorders, as a specific diagnostic and therapeutic regime could improve quality of life and life expectancy. Especially sleep apnea is a disease that has a high prevalence in this patient group and which can be treated successfully.

[Constancy of the nCPAP pressure values in the long-term monitoring of patients with obstructive sleep apnea]

A retrospective study was undertaken to discover how often mask pressures had to be adjusted over time in patients treated for sleep apnoea by continuous positive airway pressure (nCPAP). Data were analysed on 106 such patients (95 men, 11 women; mean age 55.6 [33-74] years). Their body-mass index was 31.5 +/- 5.5 kg/m2, the apnoea hypopnea index before adjustment 7.6 +/- 2.2 mbar. At the first control, after a median of 7.5 months, the pressure had to be adjusted in 55% of patients, by an average of 8.3 +/- 2.4 mbar (P < 0.001). At the second and third follow-ups (after 19.5 and 31.5 months, respectively), no further significant adjustment in mean pressure was necessary, while changes had to be made in 34.0% and 17.9%, respectively. Changes in body weight correlated with changes in pressure level (r = 0.4614 for difference between initial setting and first control; r = 0.6708 for first and second controls; r = 0.7013 for second and third controls). 61% of patients in whom mask pressure had to be altered had symptoms. Of those in whom the pressure had to be increased 82% had symptoms. Only 17% of patients requiring no change had symptoms. These findings indicate that patients on nCPAP must be monitored by polysomnography about 6 months after the initial setting, and further tests should be performed about a year apart. If body weight and feeling of well being are maintained, non-laboratory monitoring should be adequate.