Red and NIR light dosimetry in the human deep brain.

Photobiomodulation (PBM) appears promising to treat the hallmarks of Parkinson's Disease (PD) in cellular or animal models. We measured light propagation in different areas of PD-relevant deep brain tissue during transcranial, transsphenoidal illumination (at 671 and 808 nm) of a cadaver head and modeled optical parameters of human brain tissue using Monte-Carlo simulations. Gray matter, white matter, cerebrospinal fluid, ventricles, thalamus, pons, cerebellum and skull bone were processed into a mesh of the skull (158 × 201 × 211 voxels; voxel side length: 1 mm). Optical parameters were optimized from simulated and measured fluence rate distributions. The estimated µeff for the different tissues was in all cases larger at 671 than at 808 nm, making latter a better choice for light delivery in the deep brain. Absolute values were comparable to those found in the literature or slightly smaller. The effective attenuation in the ventricles was considerably larger than literature values. Optimization yields a new set of optical parameters better reproducing the experimental data. A combination of PBM via the sphenoid sinus and oral cavity could be beneficial. A 20-fold higher efficiency of light delivery to the deep brain was achieved with ventricular instead of transcranial illumination. Our study demonstrates that it is possible to illuminate deep brain tissues transcranially, transsphenoidally and via different application routes. This opens therapeutic options for sufferers of PD or other cerebral diseases necessitating light therapy.

[Cardiac imaging in (asymptomatic) diabetic patients]. / Kardiale Bildgebung beim (asymptomatischen) Diabetiker.

Coronary artery disease (CAD) plays an important role in diabetic patients because they have a very high cardiovascular mortality risk. Therefore the question arises if all diabetic patients should be screened for CAD. In patients with (a)typical angina or anginal equivalents (e.g. shortness of breath) an extended CAD evaluation is indicated. Unselected screening in diabetic patients, however, does not seem to make sense as the only large prospective randomized study in this field did not demonstrate a survival benefit in the screened patient population. It is noteworthy that preoperative risk stratification deserves special consideration in diabetic patients. If screening is considered there is the anatomic approach (calcium score, non-invasive coronary angiography) or the functional approach (stress testing, ischemia evaluation). In diabetic patients who in general should already have all the medication with respect to coronary prevention, functional rather than anatomic testing makes sense because revascularization can be considered in patients with extensive ischemia. In contrast, anatomic testing if positive would only be confirming that a medical preventive strategy is necessary. On the other hand a normal anatomic test has a very high negative predictive value. Therefore, CAD evaluation should follow an individual patient tailored approach as long as evidence-based guidelines are lacking.

Prevalence and predictors of depressive symptoms and wellbeing during and up to nine years after outpatient cardiac rehabilitation.

BACKGROUND AND AIM: Depression is an important independent prognostic variable in cardiac patients. The prevalence and predictors of depressive symptoms up to nine years after cardiac rehabilitation were studied. METHODS: Follow-up questionnaires were sent to 2199 patients who had completed a 12-week exercise-based outpatient cardiac rehabilitation (OCR) programme between June 1999 and March 2006. Medical outcome, general wellbeing, and depressive symptoms were assessed, the latter by using two screening questions according to Arrol. Patients with incomplete data due to language problems, lack of compliance and non-response were excluded. RESULTS: Complete data for analysis was available for 710 patients. The median follow up period was 46 months (Interquartile range (IQR) 22-71, min. 6 months). At follow-up, 132 patients (19%) indicated low wellbeing, whereas 81 (11%) were having depressive symptoms. Multivariate analyses revealed impaired quality of life (p <0.001), diabetes (p = 0.013) and low exercise capacity after OCR (p = 0.003) to be independent predictors of low wellbeing at follow-up. Persistent smoking (p = 0.045) as well as negative mood (p = 0.022) at the end of OCR were independent predictors of depressive symptoms at follow-up. CONCLUSIONS: In a selected patient population a mean of four years after OCR, persistent smoking, diabetes, low exercise capacity and impaired quality of life at the end of OCR were independent long term predictors of low wellbeing and depressive symptoms, rather than specific cardiac variables. This highlights the need for close cooperation between cardiovascular and psychological specialists in cardiac rehabilitation.

[Culture-negative, purulent pericarditis]. / 44-jähriger Patient mit kulturnegativer, purulenter Perikarditis.

We report about a patient with purulent pericarditis due to Neisseria meningitidis pretreated with antibiotics. Clinical signs were suggestive of pericardial tamponade. Cultures from blood and pericardial aspirate remained negative. Broad-range polymerase chain reaction from pericardial fluid detected Neisseria sp.. Latex agglutination assay from pleural fluid showed positive reaction with meningococcal antigen serogroup C. Meningococcal pericarditis without meningitis is a rare manifestation. Non-culture based diagnostic methods in patients with such severe infections and negative cultures play an important role.

[Diagnosis of coronary artery disease--part 1: general approach]. / Diagnostik der koronaren Herzkrankheit - Teil 1: Generelles Testprinzip.

Tests for the diagnosis of coronary artery disease (CAD) rely on two main diagnostic principles, that is direct visualisation of coronary anatomy or detection of stress-induced myocardial ischaemia. Whether a given test is useful for the patient's management critically depends on the clinical context, that is pre-test probability for significant CAD. Not every test is suitable for every patient. Non-invasive tests have the highest diagnostic yield in patients with chest pain and intermediate pre-test probability. In these patients, tests typically confirm the presence of CAD or make it highly unlikely. In patients with low or high pre-test probability, non-invasive tests provide hardly any added diagnostic information. However, in patients with high pre-test probability of CAD, non-invasive tests are helpful for risk stratification. In asymptomatic patients, there is no established indication for any tests apart from calculation of a global cardiovascular risk based on traditional risk factors and initiation of primary preventive measures if appropriate.

[Diagnosis of coronary artery disease - part 2: Exercise electrocardiogram and myocardial perfusion scintigraphy]. / Diagnostik der koronaren Herzkrankheit - Teil 2: Belastungs-EKG und Myokardperfusionsszintigraphie.

The principle of exercise stress test and myocardial perfusions scintigraphy (MPS) is based on the detection of exercise-induced myocardial ischaemia by ECG and non-invasive assessment of myocardial perfusion respectively, MPS being the more sensitive method. The exercise stress test is the method of choice in patients with a normal resting ECG and good exercise tolerance, whereas MPS is a suitable test for patients with abnormal resting ECG and/or exercise intolerance. Stressors for MPS included exercise, pharmacological stress, or a combination. Both exercise stress test and MPS are suitable for the evaluation of patients with chest pain and intermediate pre-test probability of significant coronary artery disease. For patients with high pre-test probability, both tests are helpful for risk stratification. Neither test makes sense for the evaluation of patients with chest pain and low pre-test probability of significant coronary artery disease or unselected asymptomatic patients.

[Diagnosis of coronary artery disease - part 3: Stress echocardiography and cardiac magnetic resonance imaging]. / Diagnostik der koronaren Herzkrankheit - Teil 3: Stress-Echokardiographie und kardiale Magnetresonanztomographie.

The diagnostic principle of stress echocardiography and cardiac magnetic resonance imaging (CMR) for the diagnosis of coronary artery disease is based on the visualisation of ischaemia-induced wall motion abnormalities. From a logistic point of view, stress echocardiography is the easiest test given that it can be performed at bedside. Both stress echocardiography and stress CMR also permit direct visualisation of myocardial perfusion at rest and during pharmacological stress (typically adenosine) using contrast administration (microbubbles for stress echocardiography, gadolinium for stress CMR). These novel methods for the visualisation of myocardial perfusion seem to provide information similar to that obtained using myocardial perfusion imaging but these techniques (particularly myocardial perfusion echocardiography) are not broadly established in daily practice yet. Similar to other non-invasive tests stress echocardiography and stress CMR have the highest diagnostic yield in patients with intermediate probability of significant coronary artery disease.

[Diagnosis of coronary artery disease - part 4: Computed tomography and coronary angiography]. / Diagnostik der koronaren Herzkrankheit - Teil 4: Computertomographie und Koronarangiographie.

Invasive coronary angiography and computed tomography (CT) coronary angiography directly visualise coronary anatomy but do not provide information about the presence of inducible myocardial ischaemia. Due to its excellent negative predictive value CT coronary angiography is a suitable test to exclude significant coronary artery disease. However, given its high rate of false positive results particularly in the presence of significant coronary calcification CT coronary angiography only rarely is a real alternative to invasive coronary angiography in clinical practice. The coronary artery calcium score (CACS) is a surrogate for the extent of coronary atherosclerosis and a possible marker of biological age but does not provide any anatomical or pathophysiological information. In asymptomatic patients a CACS of zero is associated with a very low likelihood of a significant coronary stenosis and a good prognosis. However, this is not the case in symptomatic patients, and thus, CACS does not play a significant role in the diagnostic work-up in symptomatic patients in daily routine.

Optimization of imaging before pulmonary vein isolation by radiofrequency ablation: breath-held ungated versus ECG/breath-gated MRA.

Isolation of the pulmonary veins has emerged as a new therapy for atrial fibrillation. Pre-procedural magnetic resonance (MR) imaging enhances safety and efficacy; moreover, it reduces radiation exposure of the patients and interventional team. The purpose of this study was to optimize the MR protocol with respect to image quality and acquisition time. In 31 patients (23-73 years), the anatomy of the pulmonary veins, left atrium and oesophagus was assessed on a 1.5-Tesla scanner with four different sequences: (1) ungated two-dimensional true fast imaging with steady precession (2D-TrueFISP), (2) ECG/breath-gated 3D-TrueFISP, (3) ungated breath-held contrast-enhanced three-dimensional turbo fast low-angle shot (CE-3D-tFLASH), and (4) ECG/breath-gated CE-3D-TrueFISP. Image quality was scored from 1 (structure not visible) to 5 (excellent visibility), and the acquisition time was monitored. The pulmonary veins and left atrium were best visualized with CE-3D-tFLASH (scores 4.50 +/- 0.52 and 4.59 +/- 0.43) and ECG/breath-gated CE-3D-TrueFISP (4.47 +/- 0.49 and 4.63 +/- 0.39). Conspicuity of the oesophagus was optimal with CE-3D-TrueFISP and 2D-TrueFISP (4.59 +/- 0.35 and 4.19 +/- 0.46) but poor with CE-3D-tFLASH (1.03 +/- 0.13) (p < 0.05). Acquisition times were shorter for 2D-TrueFISP (44 +/- 1 s) and CE-3D-tFLASH (345 +/- 113 s) compared with ECG/breath-gated 3D-TrueFISP (634 +/- 197 s) and ECG/breath-gated CE-3D-TrueFISP (636 +/- 230 s) (p < 0.05). In conclusion, an MR imaging protocol comprising CE-3D-tFLASH and 2D-TrueFISP allows assessment of the pulmonary veins, left atrium and oesophagus in less than 7 min and can be recommended for pre-procedural imaging before electric isolation of pulmonary veins.

Impact of contemporary emergency percutaneous coronary angioplasty for acute myocardial infarction on length of hospital stay.

QUESTIONS UNDER STUDY: Compared to thrombolysis, acute percutaneous coronary intervention (PCI) in patients with acute myocardial infarction (AMI) allows both immediate revascularisation and identification of additional relevant stenosis, so that subsequently no further risk stratification should be necessary and hospital stay shortened. Our aim was to evaluate the impact of PCI on outcome and length of hospital stay after MI compared to that in the thrombolysis era. METHODS: Retrospective evaluation in a Swiss tertiary referral centre of 105 patients with AMI undergoing emergency PCI, who initially were neither in cardiogenic shock nor transferred to another primary or secondary care hospital for further treatment. Main outcome measurement was length of overall hospital stay. Additional measurements included mortality, left ventricular function, and time point of the last major adverse cardiac event (MACE). RESULTS: Overall hospitalisation time was 11.1 +/- 6.8 days, thus being only 1.5 days shorter than in the thrombolysis era. Age above 70 or type of infarction did not influence hospitalisation time, but age below 60 years did. In-hospital mortality was 1%. Left-ventricular function was considerably impaired (<35%) in 6 patients. After the sixth hospital day, 97% of MACE had occurred. According to a validated risk score, 92% of patients belonged to a low risk group with a 30-day mortality risk of 1.4% or less and could have been discharged not later than day 6. CONCLUSIONS: Our data suggest that an early discharge strategy, although safe in low risk patients is not followed at the present time. This approach could further reduce costs without jeopardizing outcome.

[Pain killers--killing the pain or the patient?]. / Nichtsteroidale Antirheumatika und Coxibe--die sanften Herzensbrecher?

Over the last years, the coxibes were widely used as potent and well tolerated pain killers. This was in part due to the better gastrointestinal tolerability of the coxibes. On the other hand the higher cox-2 selectivity is consistent with a higher cardio-vascular event rate in patients with coxibe therapy which has been demonstrated by several studies. Side effects are probably caused by the interaction of the following factors: impact on thrombocytes, coagulation, blood vessel physiology, and blood pressure. Of note, the reported cardio-vascular adverse event rates in trials evaluating coxibes and older non-steroidal anti-inflammatory drugs was very low. Furthermore, there were no difference in fatal event rates. This underscores the need to carefully deliberate about the beneficial and potentially harmful use of these drugs. In daily practice it therefore might be suitable to still use these drugs to alleviate pain in selected patients.

Stunning and left ventricular function--how long is the ventricle knocked out? Left ventricular function correlated with ischemic burden and recovery time after stress.

PURPOSE: Little is known about the relation between severity of ischemia and duration of myocardial stunning. The aim of this study was therefore to characterize the impact of ischemia on myocardial stunning and on its duration. METHODS: 310 patients (pts) who underwent myocardial perfusion SPECT (MPS) were evaluated. MPS acquired with a rest Thallium/stress Technetium-99m sestamibi protocol were scored with respect to % myocardium ischemic. Left ventricular post-stress ejection fraction (psEF) was evaluated by the widely used QGS algorithm. Resting LVEF (rEF) was assessed by invasive ventriculography. Patient groups were then compared with respect to different extents of ischemia and different time intervals between stress and imaging (< or = 60 min and > 60 min after stress). RESULTS: 21% of pts had a normal MPS, 8% had evidence of scar, 37% had evidence of ischemia, and 34% had evidence of scar plus ischemia. Pts with normal MPS had a significantly higher psEF than pts with ischemia, 61+/-8% and 56+/-8%, respectively (p=0.006), whereas rEF was not different. Overall, pts with < or = 10% myocardium ischemic had significantly higher psEF than pts with > 10% myocardium ischemic, 53+/-11% and 49+/-9%, respectively (p=0.006), whereas rEF was not different. In pts with evidence of ischemia who underwent imaging < or = 60 min after stress testing, pts with < or = 10% myocardium ischemic had higher psEF than pts with > 10% myocardium ischemic, 60+/-7% and 53+/-8%, respectively (p=0.037). In contrast, pts with evidence of ischemia who underwent imaging > 60 min after stress testing had similar psEF irrespective of extent of ischemia (53%+/-8 in pts with < or = 10% ischemia and 54%+/-8 in pts with > 10% myocardium ischemic, p=0.12). CONCLUSIONS: Ischemia had a significant impact on psEF in patients who underwent imaging less than 1 h after stress. More than one hour after stress testing stunning seems to be less relevant in the interpretation of psEF.

Use of pro-atrial natriuretic peptide in the detection of myocardial ischaemia.

BACKGROUND: Because of its unique storage and release mechanisms allowing a very rapid response to haemodynamic changes, pro-atrial natriuretic peptide (proANP) may be a helpful cardiac marker in the detection of myocardial ischaemia. MATERIALS AND METHODS: A total of 260 consecutive patients with suspected myocardial ischaemia referred for rest/ergometry myocardial perfusion single-photon emission computed tomography (SPECT) were enrolled. Levels of plasma proANP were determined before and 1 min after maximal exercise. RESULTS: Baseline proANP and peak exercise proANP were significantly higher in patients with myocardial ischaemia as compared to those without ischaemia (median, 82 [IQR, 57-112] vs. 67 [IQR, 50-106] pmol L(-1), P = 0.007; and 89 [IQR, 65-121] vs. 78 [IQR, 57-116] pmol L(-1), P = 0.033). The area under the ROC curve for baseline proANP was 0.597 (95% CI, 0.527-0.667), as compared to 0.577 (95% CI, 0.507-0.648) for peak exercise proANP. Exercise-induced changes in proANP were similar in patients with and without myocardial ischaemia, and showed no correlation with the extent of myocardial ischaemia. CONCLUSIONS: Baseline proANP and peak exercise proANP are significantly higher in patients with myocardial ischaemia. However, because of considerable overlap in proANP levels between patients with and without myocardial ischaemia, neither measurement seems helpful in the detection of myocardial ischaemia in clinical practice.

Value of routine holter monitoring for the detection of paroxysmal atrial fibrillation in patients with cerebral ischemic events.

BACKGROUND AND PURPOSE: Holter monitoring for the detection of paroxysmal atrial fibrillation (PAF) is a routine procedure after cerebral ischemic events, although its value is unknown. The aim of this study was to evaluate the incidence of PAF and its impact on drug treatment modifications in this population. METHODS: Retrospective evaluation of all Holter ECGs in patients with cerebral ischemic events was done. Chart analysis with regard to drug treatment modification and cardiovascular drug therapy was performed in all patients. RESULTS: Between January 2000 and December 2002, 425 hospitalized patients (median age, 68 years) had routine Holter ECG after a cerebral ischemic event. PAF was diagnosed in 9 patients (2.1%): in 2, oral anticoagulation was contraindicated; 1 had severe carotid stenosis as an additional risk factor; 1 had PAF but was on oral anticoagulation for basilar thrombosis; 2 had had PAF before and were on aspirin; and 3 had a new diagnosis of PAF. The last 5 patients were put on oral anticoagulation. Thus, routine Holter ECG resulted in drug treatment modification in only 5 of 425 patients (1.2%). CONCLUSIONS: PAF in cerebral ischemic event patients has a low incidence and, if diagnosed, rarely leads to drug modification. Therefore, routine Holter monitoring for PAF screening is not recommended in this patient population.

Elevated troponin levels in absence of coronary artery disease after supraventricular tachycardia.

Generally speaking elevated troponin levels are consistent with the diagnosis of acute coronary syndrome and haemodynamically relevant coronary artery stenosis. However, they may also point to minor myocardial injury in other circumstances. Four patients with elevated troponin levels after supraventricular tachycardia without evidence of coronary artery disease and very low risk scores for acute coronary syndrome are described and discussed.