Reduced striatal D2 receptor binding in myoclonus-dystonia

PURPOSE

To study striatal dopamine D(2) receptor availability in DYT11 mutation carriers of the autosomal dominantly inherited disorder myoclonus-dystonia (M-D).

METHODS

Fifteen DYT11 mutation carriers (11 clinically affected) and 15 age- and sex-matched controls were studied using (123)I-IBZM SPECT. Specific striatal binding ratios were calculated using standard templates for striatum and occipital areas.

RESULTS

Multivariate analysis with corrections for ageing and smoking showed significantly lower specific striatal to occipital IBZM uptake ratios (SORs) both in the left and right striatum in clinically affected patients and also in all DYT11 mutation carriers compared to control subjects.

CONCLUSIONS

Our findings are consistent with the theory of reduced dopamine D(2) receptor (D2R) availability in dystonia, although the possibility of increased endogenous dopamine, and consequently, competitive D2R occupancy cannot be ruled out.

Calcium scoring using 64-slice MDCT, dual source CT and EBT: a comparative phantom study

Purpose Assessment of calcium scoring (Ca-scoring) on a 64-slice multi-detector computed tomography (MDCT) scanner, a dual-source computed tomography (DSCT) scanner and an electron beam tomography (EBT) scanner with a moving cardiac phantom as a function of heart rate, slice thickness and calcium density. Methods and materials Three artificial arteries with inserted calcifications of different sizes and densities were scanned at rest (0 beats per minute) and at 50–110 beats per minute (bpm) with an interval of 10 bpm using 64-slice MDCT, DSCT and EBT. Images were reconstructed with a slice thickness of 0.6 and 3.0 mm. Agatston score, volume score and equivalent mass score were determined for each artery. A cardiac motion susceptibility (CMS) index was introduced to assess the susceptibility of Ca-scoring to heart rate. In addition, a difference (Δ) index was introduced to assess the difference of absolute Ca-scoring on MDCT and DSCT with EBT. Results Ca-score is relatively constant up to 60 bpm and starts to decrease or increase above 70 bpm, depending on scoring method, calcification density and slice thickness. EBT showed the least susceptibility to cardiac motion with the smallest average CMS-index (2.5). The average CMS-index of 64-slice MDCT (9.0) is approximately 2.5 times the average CMS-index of DSCT (3.6). The use of a smaller slice thickness decreases the CMS-index for both CT-modalities. The Δ-index for DSCT at 0.6 mm (53.2) is approximately 30% lower than the Δ-index for 64-slice MDCT at 0.6 mm (72.0). The Δ-indexes at 3.0 mm are approximately equal for both modalities (96.9 and 102.0 for 64-slice MDCT and DSCT respectively). Conclusion Ca-scoring is influenced by heart rate, slice thickness and modality used. Ca-scoring on DSCT is approximately 50% less susceptible to cardiac motion as 64-slice MDCT. DSCT offers a better approximation of absolute calcium score on EBT than 64-slice MDCT when using a smaller slice thickness. A smaller slice thickness reduces the susceptibility to cardiac motion and reduces the difference between CT-data and EBT-data. The best approximation of EBT on CT is found for DSCT with a slice thickness of 0.6 mm.

[Against coronary balloon dilatation in small hospitals]

The Dutch Health Council report on 'Invasive cardiac procedures' [Bijzondere interventies aan her hart] recommends, for reasons of quality, efficiency and patient safety, that cardiac surgery, percutaneous coronary interventions, and the invasive treatment of cardiac rhythm disorders be concentrated in a limited number of fully equipped cardiac centres. Small hospitals should therefore not carry out invasive cardiac procedures.

[Dobutamine therapy at home under the guidance of a nurse practitioner, either as a bridge to cardiac transplantation or as destination therapy in severe heart failure]

OBJECTIVE

To evaluate the results of intravenous dobutamine therapy at home for ambulatory patients with severe heart failure.

DESIGN

Retrospective.

METHOD

Data were retrieved for the 40 patients that had been treated with intravenous dobutamine at home during the period from 1 January 1994 until mid-November 2006 at the Thorax Centre of Groningen University Medical Centre, The Netherlands. The patients were guided by a nurse practitioner.

RESULTS

The study group comprised 31 men and 9 women. The 22 patients on the waiting list for a heart transplant had an average age of 49 years. For the other 18 patients, on average 63 years old, it was destination therapy. The mean administered dosage ofdobutamine was 4 microg/kg/ min (range: 2-10). Pre-transplantation and destination therapy were given for an average of 3.5 and 1.5 months, respectively. A successful transplantation was performed in 14 (64%) of the 22 waiting-list candidates; 2 patients were still on the waiting list and 6 died while on the waiting list. Intravenous access complications and ICD shocks each occurred in 6 (15%) patients. The quality of life was reasonable to fair in the waiting-list patients and moderate to reasonable in those given destination therapy. The costs for medication and hire of the infusion pump were Euro 450 per month.

CONCLUSION

Dobutamine infusion therapy at home under the guidance of a nurse practitioner, either as a bridge to cardiac transplantation or as destination therapy in patients with severe heart failure, appeared safe, feasible and not expensive.

[Benefits and risks of drug-eluting stents]

The March 8, 2007-issue of the New England Journal of Medicine contained 5 original articles, 2 commentaries and 1 editorial on drug-eluting coronary stents versus bare metal stents. Over the past 5 years, multiple randomised, controlled trials have shown that drug-eluting stents reduce recurrent stenosis and the need for additional revascularisation procedures. Drug-eluting stents are now used in a large proportion of percutaneous coronary interventions. Following publications reporting a risk of late thrombosis with sudden occlusion, the promises and uncertainties regarding the benefits and risks are now heavily debated. It can be concluded that these first-generation drug-eluting stents, provided that they are used for indications in accordance with the randomised trials, result in a clear reduction in the need for additional revascularisation procedures without an effect on long-term case fatality and myocardial infarction. There is a small but serious risk of sudden thrombosis and occlusion. The task for the future will be to develop stents that do reduce recurrent stenosis but allow a normal endothelisation of the treated coronary artery segment. When drug-eluting stents have reached that stage, they will be clearly advantageous.

Troponin T elevation and prognosis after multivessel compared with single-vessel elective percutaneous coronary intervention

BACKGROUND.: Although techniques for percutaneous coronary intervention (PCI) have improved, patients with PCI of more vessels may still have an increased risk. We performed a prospective observational study evaluating the differences between multivessel and single-vessel procedures according to postprocedural troponin T (TnT) elevation and events during follow-up. METHODS.: The study included 713 patients without elevated TnT (<0.05 ng/ml) before PCI. Primary endpoint was the combined endpoint of death, myocardial infarction, stroke, repeat coronary angiography and readmission for anginal symptoms during the mean follow-up of 10.9 months. RESULTS.: TnT after PCI was elevated in 150 patients (21%) and was significantly associated with an increased incidence of the primary endpoint (RR 1.55, 95% CI 1.01 to 2.38). PCI of more than one vessel was performed in 146 patients (20%). These patients more often had increased TnT levels after the procedure (31.5 vs. 18.3%, p=0.001) and an increased incidence of the primary endpoint during follow-up (28 vs. 19%, p=0.01). After multivariable analysis, multivessel PCI was a statistically significant predictor of postprocedural TnT increase (OR 1.90, 95% CI 1.17 to 3.06). Multivessel PCI was also associated with an increased risk of the primary endpoint (OR 1.73, 95% CI 1.18 to 2.52), but after adjusting for multivessel disease this association was not statistically significant (OR 1.42, 95% CI 0.92 to 2.19). CONCLUSION.: Elective PCI of more vessels in one session is, in comparison with single-vessel PCI, more often associated with postprocedural troponin T rise and a (nonsignificantly) higher incidence of cardiac events during follow-up. Whether staged PCI is associated with less morbidity has to be assessed. (Neth Heart J 2007;15:178-83.).

Glucose dysregulation in nondiabetic patients with ST-elevation myocardial infarction: acute and chronic glucose dysregulation in STEMI

BACKGROUND

Admission hyperglycaemia is associated with an increased risk of mortality after myocardial infarction. Whether long-term glucose dysregulation (assessed by HbA1c) is more important than acute hyperglycaemia is unknown. We evaluated the prognostic value of admission glucose and HbA1c levels in nondiabetic patients with ST-segment elevation acute myocardial infarction (STEMI).

METHODS

In 504 unselected, consecutive patients with STEMI, glucose and HbA1c levels were measured on admission. Glucose was categorised as <11.1 mmol/l (n=422) and >or= 11.1 mmol/l (n=82). HbA1c levels were categorised as <6.0% (n=416) and >or=6.0% (n=88). Mean follow-up was 1.6+/-0.6 years.

RESULTS

Patients with hyperglycaemia on admission were comparable with those with normoglycaemia. However,patients with HbA1c >or=6.0%, as compared with those with HbA1c <6%, were older, were more often on beta-blockers and more frequently had multivessel disease. Thirty-day mortality in the subsequent glucose categories (<11.1 mmol/l and >or=11.1 mmol/l) was 4% and 19% (p<0.001) and in the subsequent HbA1c categories (<6% and >or=6%) was 5% and 12% (p=0.03). After multivariable analyses, admission glucose (OR 4.91,95% CI 2.03 to 11.9, p< 0.001) but not HbA1c (OR 1.33, 95%CI 0.48 to 3.71, p=0.58) was significantly associated with 30-day mortality. Among 30-day survivors, neither admission glucose nor HbA1c were predictors of long-term mortality.

CONCLUSION

Elevated admission glucose is an important predictor of 30-day outcome after STEMI, while prior long-term glucose dysregulation is a covariate of other high-risk clinical characteristics. Among 30-day survivors, neither admission blood glucose nor HbA1c were predictors of long-term outcome.

[Myocardial contusion after blunt thoracic trauma: possible indication for rhythm observation]

A 65-year-old man had a pneumohaemothorax and fractured ribs after an automobile accident. Troponine concentrations were normal and the initial electrocardiographic abnormalities resolved within 24 hours. A 46-year-old man who was also in an automobile accident developed a seat-belt haematoma and lung oedema. Troponine concentrations were increased, the electrocardiogram was abnormal and transthoracic ultrasound revealed severe myocardial contusion. After a few weeks of treatment, both patients were discharged without cardiac complications. It is clinically important to identify patients at risk of developing myocardial contusion following blunt thoracic trauma. A combination oftroponine and electrocardiography is necessary to differentiate between risk categories. Echocardiography has a role in haemodynamically unstable patients and whenever the clinical condition of the patient deteriorates. A structured approach to screening and evaluation, as presented in an algorithm, can be used as a guide in the follow-up of patients with myocardial contusion.

Circumflex artery-related acute myocardial infarction: limited ECG abnormalities but poor outcome

BACKGROUND

Circumflex (CX) artery-related myocardial infarction (MI) is less well represented in trials on ST-elevation acute myocardial infarction (STEMI), most often due to the absence of significant ST-segment elevation, and therefore the outcome of these patients is less well known. We aimed to compare the outcome of patients with CX versus right coronary artery (RCA) related STEMI in a large cohort of patients treated with primary angioplasty.

METHODS

A total of 1683 consecutive patients with STEMI were studied. Patients who lacked STsegment elevation were also included if they had persistent chest pain with signs of ischaemia or regional wall motion abnormalities on echocardiography. Coronary angioplasty was performed according to standard procedures. After the intervention, all patients received aspirin and clopidogrel or ticlopidine.

RESULTS

The infarct-related vessel was the CX in 229 patients (14%) and the RCA in 600 patients (36%). No differences in baseline characteristics were present. Mean extent of ST-segment elevation or deviation was significantly higher in patients with the RCA as infarct-related vessel. Enzymatic infarct size was significantly higher in the CXrelated MI (1338+/-1117 IU/l vs. 1806+/-1498 IU/l, p<0.001). Left ventricular ejection fraction <45% was more often present in patients with CXrelated MI (37 vs. 26%, p<0.01). Both short- and long-term mortality were significantly higher in the CX-related MI.

CONCLUSION

This study emphasises the fact that CX-related infarction has a worse prognosis compared with RCA-related infarction. (Neth Heart J 2007;15:286-90.).

Discordance between anatomical and functional coronary stenosis severity

BACKGROUND.: New developments have made 16-slice multidetector computed tomography (MDCT) a promising technique for detecting significant coronary stenoses. At present, there is a paucity of data on the relation between fractional flow reserve (FFR) measurement and MDCT stenosis detection. OBJECTIVE.: The aim of this study was to investigate the relation between the anatomical severity of coronary artery disease detected by MDCT and functional severity measured by fractional flow reserve (FFR). METHODS.: We studied 53 patients (39 men and 14 women, age 62.5+/-8.1 years) with single-vessel disease scheduled for percutaneous coronary intervention (PCI). All patients underwent MDCT scanning one day prior to PCI and FFR was measured before PCI in the target vessel. RESULTS.: MDCT analysis could be performed in 52 of 53 patients (98.1%) and all patients had adequate FFR and quantitative coronary angiography (QCA) measurements. The mean stenosis diameters calculated by MDCT and QCA were 67.0+/-11.6% and 60.8+/-11.6% respectively. No significant relation was found between MDCT and QCA (r=0.22, p=0.12) The mean FFR in all patients was 0.67+/-0.18. A relation of r=-0.46 (p=0.0006) between QCA and FFR was found. In contrast, no relation between MDCT and FFR could be demonstrated (r=-0.09, p=0.50). Furthermore, a high incidence of false-positive and false-negative findings was present in both diagnostic modalities. CONCLUSION.: There is no clear relation between the anatomical and functional severity of coronary artery disease as defined by MDCT and FFR. Therefore, functional assessment of coronary artery disease remains mandatory for clinical decisionmaking. (Neth Heart J 2007;15:5-11.).

Haemodynamic patterns in ST-elevation myocardial infarction: incidence and correlates of elevated filling pressures

OBJECTIVES.: We sought to study the incidence and clinical correlates of elevated filling pressures in ST-elevation myocardial infarction (STEMI) patients, without physical signs of heart failure and treated with primary coronary angioplasty. BACKGROUND.: Haemodynamic data, as measured with a Swan-Ganz catheter, are not routinely obtained in STEMI patients. At admission, low blood pressure, increased heart rate, sweating, increased respiration rate, rales, oedema, and a third heart sound are indicative of heart failure. METHODS.: All consecutive STEMI patients were monitored by a Swan-Ganz catheter and central venous pressure (CVP), pulmonary capillary wedge pressure (PCWP), pulmonary artery pressure (PAS) and cardiac index (CI) were measured. To investigate the clinical correlates of the haemodynamic status patients were classified according to previously defined haemodynamic criteria. RESULTS.: We studied 90 patients, aged 60.5+/-13.1 year, 76% were male. Mortality at 30 days was 2/90 (2.2%). Patients with impaired haemodynamics presented later and had larger myocardial infarct sizes. CVP, PCWP and PAS were above normal in 36 (40%) patients. CONCLUSION.: A large proportion of STEMI patients without physical signs of heart failure have elevation of right- as well as left-sided cardiac filling pressures. (Neth Heart J 2007;15:95-9.).

Long-term outcome after heart transplantation performed in the University Medical Centre Groningen

BACKGROUND

Ten years ago, there was a difference of opinion about the suitability of ventilated patients with end-stage cardiac failure for heart transplantation (HTX). Although guidelines at that time qualified mechanical ventilation as a contraindication, we thought those patients could be candidates for HTX. In the same period a number of other patients received a donor heart in our centre. In this article we describe the clinical course and survival after these procedures.

METHODS

We performed a retrospective study using our post HTX database. All patients undergoing transplants in our hospital were selected. Patients underwent echocardiography, scintigraphy (MUGA), ergo-spirometry (VO₂ peak), blood tests and completed a quality of life questionnaire (SF-36). All tests were completed in the 1st quarter of 2006.

RESULTS

Eight patients were identified; three were mechanically ventilated at the time of HTX. All eight patients were treated according to the standard protocol. Repeated surveillance cardiac biopsies were taken. One patient died 3.5 years after HTX due to an acute myocardial infarction. Seven patients, including the three patients on a ventilator at the time of the HTX, are alive, resulting in a survival rate of 88%. The current median survival time is 126 months (range 55 to 184 months). All patients are in good cardiac condition. The SF-36 domains of social functioning and mental health show high scores, the average score of general health and vitality is moderate.

CONCLUSION

Survival of our eight transplanted patients after a median period of ten years was 88%, which is at least comparable with data from larger series. This finding suggests that HTX can be performed effectively and safely in a low volume centre. The finding that all three patients on a ventilator prior to HTX are alive is remarkable. It appears that mechanical ventilation is not always an absolute contraindication for HTX.

Quantification of global left ventricular function: comparison of multidetector computed tomography and magnetic resonance imaging. a meta-analysis and review of the current literature

Cardiac morbidity and mortality are closely related to cardiac volumes and global left ventricular (LV) function, expressed as left ventricular ejection fraction. Accurate assessment of these parameters is required for the prediction of prognosis in individual patients as well as in entire cohorts. The current standard of reference for left ventricular function is analysis by short-axis magnetic resonance imaging. In recent years, major extensive technological improvements have been achieved in computed tomography. The most marked development has been the introduction of the multidetector CT (MDCT), which has significantly improved temporal and spatial resolutions. In order to assess the current status of MDCT for analysis of LV function, the current available literature on this subject was reviewed. The data presented in this review indicate that the global left ventricular functional parameters measured by contemporary multi-detector row systems combined with adequate reconstruction algorithms and post-processing tools show a narrow diagnostic window and are interchangeable with those obtained by MRI.

The benefit of 64-MDCT prior to invasive coronary angiography in symptomatic post-CABG patients

PURPOSE

The purpose of this study is to assess the diagnostic accuracy of 64-MDCT in symptomatic patients after CABG and to explore the advantages of the 64-MDCT results on the CAG procedure.

MATERIAL AND METHODS

From December 2004 until August 2005, 34 post-CABG patients (29 men, mean age 63.5 +/- 8.5 years) with 69 coronary artery bypass grafts were scanned on a 64-MDCT (Somatom Sensation 64, Siemens AG, Forchheim, Germany) prior to CAG. Angiograms and 64-MDCT images were evaluated for the existence of occlusions or significant stenosis (>or=50% lumen reduction) in bypass grafts and native coronary arteries.

RESULTS

64-MDCT had a sensitivity, a specificity, and a diagnostic accuracy of 100% for occlusion detection. For stenosis detection, sensitivity was 100%, specificity 98.7% and diagnostic accuracy 98.7%. For detecting significant stenosis in native coronary arteries, 64-MDCT had a sensitivity of 80.0%, specificity of 90.8%, and a diagnostic accuracy of 87.1%. Seventeen patients (50.0%) did not need invasive treatment, 14 patients (41.2%) underwent a percutaneous coronary intervention (PCI), and 3 patients (8.8%) underwent surgery. Treatment advice based on 64-MDCT was correct in 88.2% of patients and when 64-MDCT results would have been known 58.8% of diagnostic CAG procedures could have been prevented.

CONCLUSION

In conclusion, 64-MDCT has a high diagnostic accuracy in detecting bypass graft stenosis and occlusions, and 64-MDCT based treatment advice was correct in 88.2% of patients.

Echocardiographic and electron beam tomographic assessment of stenosis in patients with aortic valve disease: gradient versus valve area

BACKGROUND

Transthoracic echocardiography (TTE) is routinely used to evaluate aortic valve stenosis. However, it does not give reliable results in every patient. There is growing interest in electron-beam tomography (EBT) as a noninvasive cardiac imaging technique. The usefulness of EBT to evaluate aortic stenosis has yet to be evaluated.

AIM

To compare EBT with TTE in assessing severity of aortic stenosis.

METHODS

In total 47 patients (18 females, 29 males) underwent a contrast-enhanced EBT scan and TTE within 6±20 days. The calcium score of the aortic valve was determined and the aortic valve area (AVA) was measured by planimetry. A complete TTE study, during which the peak pressure gradient across the aortic valve was measured, was performed in all patients by an experienced sonographer.

RESULTS

There was a significant correlation between AVA assessed by EBT and peak pressure gradient (r=-0.38, p=0.009). The calcium score of the aortic valve assessed by EBT correlated with peak pressure gradient (r=0.48, p=0.001).

CONCLUSION

EBT is a useful noninvasive method to evaluate the severity of aortic stenosis. It holds the possibility of assessing the AVA as well as quantification of the degree of calcification.

Long-term clinical outcome of patients with diabetes proposed for coronary revascularisation

BACKGROUND

The optimal method of revascularisation in diabetic patients with coronary artery disease (CAD) remains controversial. It was our aim to evaluate long-term outcome in diabetic patients with CAD in daily practice, in whom an invasive approach was considered.

METHODS

A prospective follow-up study of patients with CAD in whom a coronary revascularisation procedure was considered. Follow-up data were obtained on the vital status up to ten years after inclusion.

RESULTS

Of the 872 included patients, a total of 107 patients (12%) had diabetes. Patients with diabetes were older and more frequently female. Long-term mortality was higher in diabetics than nondiabetics (36 vs 25%, p = 0.01). This association was observed in both medically treated patients (65 vs 31%, p = 0.01) and in those treated by percutaneous coronary intervention (41 vs 24%, p = 0.02). There was, however, no difference in mortality in diabetes vs nondiabetes patients after coronary artery bypass grafting (24 vs 24%, p = 0.89). Multivariate analysis did not change these findings.

CONCLUSION

Diabetic patients with significant CAD had a higher long-term mortality compared with patients without diabetes. In patients with diabetes, survival was highest after coronary artery bypass grafting and appeared to be comparable between diabetic and nondiabetic patients. Complete revascularisation may decrease the influence of diabetes on survival.

The effect of electrical neurostimulation on collateral perfusion

BACKGROUND/OBJECTIVES

Clinical data have shown that electrical neurostimulation may improve myocardial ischaemia. Our aim was to investigate the possible effect of electrical neurostimulation on collateral perfusion.

METHODS

Thirty patients with stable angina and significant single-vessel coronary artery disease scheduled for elective percutaneous coronary intervention (PCI) were randomised into three groups. In all patients two balloon inflations were performed, one for predilatation of the lesion, the second for stent delivery. Group one received active neurostimulation during the first ischaemic episode (predilatation), group two during the second ischaemic episode (stent delivery), and group three received placebo neurostimulation continuously. During both ischaemic episodes the collateral flow index was determined.

RESULTS

No significant differences were found between active, inactive or placebo neurostimulation. In a post-hoc analysis the patients were stratified for presence or absence of significant collaterals. In patients with pre-existing significant collaterals, the collateral flow index was significantly higher during active neurostimulation compared with inactive neurostimulation (p=0.012) and compared with the merged inactive and placebo groups (p=0.011).

CONCLUSION

The present data show no effect of electrical neurostimulation on collateral perfusion in patients with single-vessel disease. In a post-hoc analysis in patients with evidence of collaterals, defined as a collateral flow index of >0.24, an increase in collateral perfusion was found during electrical neurostimulation.