Reevaluation of the Griess method for determining NO/NO2- in aqueous and protein-containing samples

Nitric oxide (NO) is an important intracellular and extracellular signal substance. Nitrite is one product of the oxidative metabolism of NO. The purpose of this study was to establish a simple method of determining nitrite (NO2-) to provide a means of estimating the endogenous formation of NO or NO2-. A flow injection analysis (FIA) based on the Griess reaction was developed for this purpose. Using a standard additive method, it is possible to eliminate matrix effects such as those that can occur in samples containing protein. This measuring method is suitable for measurements in effluates or protein-rich cellular supernatants. The sensitivity of the method is 2 nmol/L for samples in aqueous phases and 8 nmol/L for protein-containing phases. The two-point discrimination is 2 nmol/L. A linear correlation between nitrite and signal level can be demonstrated over a range of 0.002-5 micromol/L. Reproducibility, including sample preparation and analysis, can be specified with a coefficient of variation (C.V.) of 6.7%. Day-to-day variability for identical samples 0.8% (C.V.). This study presents examples of the application of this method (measurements in blood samples and in isolated perfused hearts) and compares them to established methods of measuring NO and NO2. We found the FIA method to be equally sensitive as NO measurement by means of oxyhemoglobin assay. The FIA method is seven times more sensitive than HPLC methods, and its design is significantly simpler. Compared to the traditional Griess method, its sensitivity is higher by a factor of 500. With its high sensitivity, high reproducibility, and its unsurpassed low susceptibility to interference, this method of analysis provides a means of reliably determining nitrite concentration as a marker of NO formation in various matrices. Therefore, it can be a valuable instrument in experimental and clinical studies to determine the physiologic and pathophysiologic relevance of NO.

Coronary artery bypass grafting with an expanded polytetrafluoroethylene graft

BACKGROUND

We report our experience with the Perma-Flow aortocoronary-right heart graft in 15 patients in whom autologous conduits were not available.

METHODS

Fifteen patients received 39 coronary anastomoses--10 to left anterior descending coronary artery branches, 15 to circumflex coronary artery branches, and 14 to branches of the right coronary artery. Early angiography was done in 11 patients.

RESULTS

One patient died on postoperative day 17 of multiorgan failure. The graft was patent at postmortem examination. Of 30 coronary anastomoses at risk, 24 were patent. Three connections to the left anterior descending system were occluded in patients with an additional internal mammary artery graft to the same coronary system, and three connections to the circumflex system were occluded in patients with a history of major posterior infarction. Three of five distal anastomoses to the right atrial appendage were occluded, whereas all six connections to the superior vena cava were patent. None of the patients had shown recurrent angina at a mean follow-up of 10.9 months (range, 2-39 months).

CONCLUSIONS

The synthetic Perma-Flow coronary graft appears to be a safe alternative in patients in whom arterial or venous conduits are not available. Competitive flow may lead to anastomotic occlusions. The appropriate site for the distal arteriovenous fistula seems to be the superior vena cava.

A prognostic computer model to individually predict post-procedural complications in interventional cardiology: the INTERVENT Project

AIMS

The purpose of this part of the INTERVENT project was (1) to redefine and individually predict post-procedural complications associated with coronary interventions, including alternative/adjunctive techniques to PTCA and (2) to employ the prognostic INTERVENT computer model to clarify the structural relationship between (pre)-procedural risk factors and post-procedural outcome.

METHODS AND RESULTS

In a multicentre study, 2500 data items of 455 consecutive patients (mean age: 61.1+/-8.3 years: 33-84 years) undergoing coronary interventions at three university centres were analysed. 80.4% of the patients were male, 16.7% had unstable angina, and 5.1%/10.1% acute/subacute myocardial infarction. There were multiple or multivessel stenoses in 16.0%, vessel bending >90 degrees in 14.5%, irregular vessel contours in 65.0%, moderate calcifications in 20.9%, moderate/severe vessel tortuosity in 53.2% and a diameter stenosis of 90%-99% in 44.4% of cases. The in-lab (out-of-lab) complications were: 0.4% (0.9%) death, 1.8% (0.2%) abrupt vessel closure with myocardial infarction and 5.5% (4.0) haemodynamic disorders.

CONCLUSION

Computer algorithms derived from artificial intelligence were able to predict the individual risk of these post-procedural complications with an accuracy of >95% and to explain the structural relationship between risk factors and post-procedural complications. The most important prognostic factors were: heart failure (NYHA class), use of adjunctive/alternative techniques (rotablation, atherectomy, laser), acute coronary ischaemia, pre-existent cardiac medication, stenosis length, stenosis morphology (calcification), gender, age, amount of contrast agent and smoker status. Pre-medication with aspirin or other cardiac medication had a beneficial effect. Techniques, such as laser angioplasty or atherectomy were predictors for post-procedural complications. Single predictors alone were not able to describe the individual outcome completely.

Evolving short-term and long-term mechanical assist for cardiac-failure -- a decade of experience in Münster

Technological advances and growing expertise has lead to referral of much sicker patients with a greater incidence of heart failure prior to and after cardiac surgical procedures. The diversity of the heart failure patient cohort mandates a differentiated protocol for mechanical support adapted to the clinical requirements. It is desirable to have appropriate mechanical support available for different circumstances of heart failure. In this paper, we review the first decade of the Muenster University Hospital experience with the use of intra-aortic ballon pump, extracorporal membrane oxygenators, short term uni- and biventricular assist systems such as Thoratec and Medos devices, as well as long term left ventricular assist systems such as the TCI Heartmate and the Novacor system. The patient profiles, indications, contraindications, and future trends are reviewed within the framework of a contemporary university hospital Servive.

Selection and outcome of ventricular assist device patients: the Muenster experience

BACKGROUND

Because the number of patients on the waiting list for transplantation is increasing and the stagnation in the number of organs donated has led to a more restrictive listing for transplantation, an increased fraction of patients needs to be bridged mechanically. We examined the hypothesis that selection of these patients with regard to urgency status is critical in determining outcome.

METHODS

A cohort of 631 patients referred for transplantation to our center between January 1, 1990, and December 31, 1996, was analyzed. Two hundred ninety-seven patients were listed for transplantation and 157 were given transplantation. Forty-one patients had to undergo ventricular assist device implantation (n=34, Novacor; n=6, TCI Heartmate; n=1, Medos), 39 for bridging to transplantation and 2 for permanent support. Initial transplantation evaluation data were analyzed in 3 subgroups (elective bridging, urgent bridging, emergency bridging) and compared with another and with other patients referred for transplantation, specifically those who did not have to be bridged on the waiting list.

RESULTS

Patients who underwent elective or urgent assist device bridging were younger and more compromised than the rest of patients accepted on the waiting list (higher functional class, lower mean arterial pressure, lower cardiac index, lower serum sodium, higher pulmonary capillary wedge pressure). In the elective group, overall survival including perioperative mortality rate was better than in the urgent/emergency group and at least as good as in patients who were stable on the waiting list and did not undergo heart transplantation during follow-up. This should prompt cardiologists and cardiac surgeons to consider assist device implantation earlier.

Failure to confirm ferritin and caeruloplasmin as risk factors for the angiographic extent of coronary arteriosclerosis

BACKGROUND

It has been suggested that iron overload, as assessed by increased serum ferritin concentration, may be a risk factor for coronary artery disease (CAD). Recent studies have reported conflicting data on the role of ferritin and other parameters of oxidative metabolism in CAD.

OBJECTIVE

The aim of this study was to assess the relation between the extent of CAD and parameters of oxidation.

METHODS

We studied 275 patients (208 men aged 55.1 +/- 9.6 years and 67 women aged 54.6 +/- 10.0 years) who underwent coronary angiography or percutaneous transluminal coronary angioplasty for the first time. The parameters assessed were: iron, ferritin, transferrin, copper, caeruloplasmin and lipid. Cinefilms were assessed by the use of three scores: (1) Vessel score: 0-3 points; 1 point for each of the three main coronary arteries with a stenosis >70%. (2) Stenosis score: 0-32 points; the coronary artery tree was divided into eight segments that were scored 1-4 points per segment with respect to the maximal degree of stenosis. (3) Extent score: 0-100 points; extent of diffuse coronary lesions in each segment in relation to the length of the vessel. Multiple regression analyses were used to evaluate the results.

RESULTS

Total cholesterol and low-density lipoprotein cholesterol (P < 0.001) in women, low-density lipoprotein cholesterol (P < 0.05) in men, and patient age showed a significant correlation with all three scores, but none of the parameters of oxidative metabolism (iron, transferrin, ferritin, copper, caeruloplasmin) correlated significantly with any of the three scores.

CONCLUSION

This study demonstrated a correlation between lipoproteins and the angiographic extent of CAD, but did not confirm a role for serum ferritin and other oxidative parameters as risk factors for the extent of CAD.

T-cell and monocyte subsets, inflammatory molecules, rejection, and hemodynamics early after cardiac transplantation

BACKGROUND

In the early period after cardiac transplantation, differential diagnosis of graft failure due to rejection, infection, and other causes is important but difficult.

METHODS

In 22 consecutive patients undergoing heart transplantation, we prospectively determined levels of interleukin-6 as well as T-cell and monocyte subsets at eight points in time during biopsy and right heart catheterization and within 12 hr of echocardiography during the first 3 months after transplantation.

RESULTS

Worse hemodynamic parameters, as characterized by dichotomization according to median values (pulmonary capillary wedge pressure >10 mmHg, mean pulmonary arterial pressure > 18 mmHg, pulmonary vascular resistance > 115 dyn x sec x cm(-5), right atrial pressure > 5 mmHg, cardiac index <3 L/min/m2, early mitral deceleration time < 135 msec, and isovolumic relaxation time <80 msec), were associated with higher levels of interleukin-6, C-reactive protein, polymorphonuclear cells, CD71+/CD14+ monocytes, and IgM levels and, in contrast, with lower levels of immunocompetence markers such as CD3+ T cells, CD4+ T cells, CD8+ T cells, CD3+/CD25+ T cells, CD4+/ CD45RO+ T cells, NK cells, and lower biopsy scores.

CONCLUSION

Early after cardiac transplantation, elevated levels of inflammatory cells and soluble inflammatory molecules and lower levels of immunocompetence markers are associated with impaired allograft function in the absence of cellular rejection.

Possible relationship between heat shock protein 70, cardiac hemodynamics, and survival in the early period after heart transplantation

BACKGROUND

Heat shock proteins (HSPs) are produced by cells in response to a wide variety of stresses. To determine a possible relationship between hemodynamic parameters and HSP 70 in the early postoperative period after heart transplantation, we examined immunohistochemically the inducible HSP 70 (anti-HSP 72) response in human heart biopsies, as well as the effect of myocardial rejection on HSP.

METHODS

A total of 105 routinely processed endomyocardial biopsies from 15 consecutive patients who underwent heart transplantation were examined. Analysis of hemodynamic and echocardiographic parameters were performed within 30 min and 12 hr after the biopsies.

RESULTS

Immunohistochemically detected inducible HSP 70 was mainly located in the cytoplasm and nucleus/nucleolus of cardiomyocytes. Two specimens additionally showed HSP 70-positive interstitial cells and smooth muscle cells of arteries, whereas lymphocytes were consistently negative. There was a significant relation between the echocardiographically determined increased relaxation time and positive HSP 70 staining (P < 0.011). Patients with elevated right atrial pressure (P < 0.098), as well as those with increased left ventricular end systolic diameter (P < 0.06), showed a trend to higher HSP expression. Three patients who died of sepsis or multiorgan failure showed significantly higher cytoplasmic HSP 70 expression compared with 12 patients with stable clinical course. In case of rejection, significantly more patients showed no HSP expression.

CONCLUSION

Although only five patients showed organ rejection, our results suggest an inverse relationship between HSP expression and rejection with the possibility of a role for HSP 70 as a graft marker to assess graft function.

Cardiac pacemaker infection: surgical management with and without extracorporeal circulation

BACKGROUND

Pacemaker infections are rare, but serious complications of pacemaker therapy. The generator pocket, the pacing leads, or both may be involved.

METHODS

We report on 12 patients with infected pacemaker systems. Four patients suffered from localized generator pocket infections, 6 had infected leads, and 2 patients had both. Pacemaker systems were completely removed in all patients. When the infection was limited to the generator pocket, the pacemaker system was removed at the original implantation site. Extracorporeal circulation was employed for the explantation of infected pacing leads.

RESULTS

No complications occurred in patients with localized generator pocket infections. One patient with infected leads who was preoperatively already in a serious clinical condition died of septic shock in the early postoperative period; another patient died of pulmonary complications after tricuspid valve replacement 14 months after pacemaker explantation. No recurrent infections were observed.

CONCLUSIONS

Explantation of the complete pacemaker system has proved a reliable method to eradicate infection. Complications have been rare, except in patients in a critically ill state who undergo cardiopulmonary bypass.

[Pregnancy in patients with transposition of great vessels corrected by the Mustard procedure. Report of a case and review of reported cases]

BACKGROUND

In patients after atrial switch operation (Mustard or Senning procedure) for transposition of the great arteries (TGA), the anatomic right (anterior) ventricle works as the systemic ventricle. Although this is associated with an increased rate of congestive heart failure, the prognosis for long-term survival is good. Therefore a large proportion of these patients has reached their reproductive years and consult cardiologists and obstetricians because they plan a pregnancy or are already pregnant. Because of the substantial hemodynamic changes and the increase in cardiac output during pregnancy, potential risk factors and complications have to be considered.

PATIENTS

Initiated by the presentation of a pregnant patient with TGA after surgery in our hospital, we analyzed the information referenced in MEDLINE. Including our patient, there were reports on 27 patients after the Mustard procedure with a total of 39 pregnancies. FETAL OUTCOME: Three abortions occurred during the first trimenon, another one was electively induced because of maternal cardiac deterioration. One late abortion occurred in the 23rd week of pregnancy. 35 babies (one twinpair) were born healthy without cardiovascular anomalies. MATERIAL OUTCOME: No maternal deaths occurred. Eight women developed clinical signs of systemic (= right) heart failure including all three patients with former complex TGA. Four of these patients recovered after delivery, four showed persistent reduction of physical abilities or signs of heart failure. Further complications were supraventricular tachycardias (five patients) and a high incidence of hypertension and pre-eclampsia (22% of patients).

CONCLUSION

Overall, the outcome for mothers after Mustard procedure for TGA and their children is good, but there is need for intensive and specialized follow-up.

A prognostic computer model to predict individual outcome in interventional cardiology. The INTERVENT Project

It is not yet possible to predict an individual's outcome from percutaneous transluminal coronary angioplasty or alternative/adjunctive coronary interventional techniques. The purpose of the INTERVENT project is to redefine complications associated with coronary interventions, to set up a prognostic computer model to predict individual outcome and to compare the results to those of conventional statistical techniques. 2500 data items were analysed in 455 consecutive patients (mean age: 61.1 +/- 8.3 years; range 33-84 years; 80.4% male, 16.7% unstable angina, 5.1%/10.1% acute/subacute myocardial infarction) undergoing coronary interventions at three university centres. In-lab/out-of-lab complication rates were 0.4%/0.9% (death), 1.8%/0.2% (abrupt vessel closure with myocardial infarction) and 5.5%/4.0% (haemodynamic complications). Computer algorithms derived by applying techniques from artificial intelligence were able (1) to reduce the set of possible relevant risk factors from 2500 to about 40, (2) to predict individual risk with an accuracy of > 95% and (3) to explain the structural relationship between outcome and risk factors. Patient data from two centres were used to construct and test the algorithm. Data from a third centre were used to evaluate the algorithm. The most important predictors-were acute myocardial infarction, heart failure (NYHA class > II), unstable angina, complex lesions, high low density lipoprotein cholesterol and duration of coronary heart disease. Neither age nor gender impaired the percutaneous transluminal coronary angioplasty results in acute ischaemic syndromes; however, for stable angina, procedural risk increased with age. There was little risk from primary percutaneous transluminal coronary angioplasty in acute myocardial infarction in patients with NYHA heart failure classes I-II; however, the risk was high for patients in NYHA classes > II, either with or without additional thrombolysis. Alternative/adjunctive intervention techniques were no predictors for in-lab-, but were predictors for post-procedural complications.

Long-term left ventricular assist device support: a novel pump rate challenge exercise protocol to monitor native left ventricular function

A novel, hemodynamically guided exercise protocol with two different left ventricular assist device settings in two long-term recipients is presented. This protocol allows for quantitation of the contribution of the native left ventricle to total cardiac output. It facilitates estimation of the risk associated with device dysfunction, as well as prediction of left ventricular recovery and the potential for weaning.

Heart surgery in patients aged eighty years and above: determinants of morbidity and mortality

Escalating medical costs, limitation of resources and the necessity to provide cost-effective medical care have created a need for systematic risk stratification and cost-benefit analyses in the background of an ongoing discussion. Results of heart surgery in octogenarians have been evaluated in a prospective single-center, study since 1990. 101 consecutive patients (55/ 101 = 54.5% female) aged 80 years and above (median: 81 years; interquartile range [IQR]: 80.0-82.5, total range [TR]: 80-92 years) undergoing open heart surgery at our institution between January 1990 and March 1996 were included into this prospective study. Prior to surgery, most patients were severely symptomatic being in functional NYHA classes either III (56.4%) or IV (31.7%). 61/101 (60.4%) patients underwent isolated coronary artery bypass grafting (CABG), 23 (22.8%) had aortic valve replacement (AVR), 14 patients (13.9%) had CABG combined with AVR or double valve replacement and 3 (3.0%) had mitral valve repair. Follow-up (median: 23.0 months. IQR: 10.5-39.0, TR: 1-72) was focused on long-term morbidity and quality of life. The impact of preoperative and operative risk factors on morbidity and mortality was determined by uni- and multivariate statistical analysis. The 30-days overall mortality in this study was 7.9%. The postoperative course was uneventful for 27 (26.7%) of our patients. Univariate risk factors of postoperative mortality were: left main stem disease (p < or = 0.044), ejection fraction < 45% (p < or = 0.006), preoperative intensive care unit (ICU) (p < or = 0.002), urgent or emergency operation (p < or = 0.034). The only independent predictor of operative mortality was preoperative ICU-stay (p < or = 0.008). Significant risk factors for the number of postoperative complications in the multivariate analysis were: prior stroke (p < or = 0.04), diabetes mellitus (p < or = 0.02), New York Heart Association (NYHA) class IV symptoms (p < or = 0.002) and prolonged cross-clamping time (p < or = 0.001). Mean postoperative length of stay in the ICU was 3.9 +/- 3.9 days. Late morbidity was not related to postoperative complications. Cumulative survival was 87.9%, 79.5% and 72.9% at one, two or five years, respectively. After hospital discharge, 67/93 patients (82.8%) were in NYHA functional class I or II. Cardiac surgery in very elderly patients can be performed with acceptable operative risk and a favorable long-term outcome. The individual patient risk-profile including significant co-morbid conditions and severity of the heart disease predicts not only survival but the extent of perioperative morbidity.

Progressive heterogeneity of myocardial perfusion in heart transplant recipients detected by thallium-201 myocardial SPECT

Progressive graft atherosclerosis is a serious complication in long-term survivors after heart transplantation. Coronary angiography is insensitive with regard to the early and characteristic alterations. We evaluated the progression of these abnormalities and the influence of former rejection episodes.

METHODS

Early after transplantation, 43 patients (34 men, mean age 53.7 +/- 10.7 yr) underwent stress and redistribution 201Tl myocardial SPECT after treadmill exercise. Twenty patients were followed-up to the second postoperative year, and 13 patients to the third postoperative year. Thallium-201 distribution and kinetic abnormalities were documented in a scheme enclosing 20 myocardial segments. Additionally, a score was developed that measured the degree of inhomogeneity of 201Tl distribution and the severity of perfusion defects, respectively.

RESULTS

Regarding scintigraphy, pathologic results could be found in 40% of segments (redistribution, 25%; reverse redistribution, 30%; persistent defects, 49%). Score values in heart transplant recipients differed significantly from normal controls (p < 0.001) and were comparable to patients with single vessel disease of their native hearts. Thallium-201 inhomogeneity in recipients after treatable rejection episodes did not differ from results in recipients without any biopsy-proven rejection. The follow-up of cardiac transplant patients revealed a significant increase of score values up to the third year after transplantation (p < 0.02), despite reproducible normal angiography. There was no direct correlation between score values and IVUS results, although there was a parallel trend in 10 of 12 follow-ups.

CONCLUSION

Despite normal coronary angiography, 201Tl myocardial SPECT frequently revealed pathologic results in heart transplant recipients. Scintigraphic results did not correlate with intimal thickening of epicardial coronary arteries accessible to intravascular ultrasonography in the early phase after transplantation. The presented score of inhomogeneity might reveal progressive disease possibly caused by small vessel alterations.

[Evaluation of secondary prevention of coronary heart disease. Results of the EUROSPIRE study in the Munster region]

BACKGROUND

New recommendations for secondary prevention of coronary heart disease (CHD) were issued by the European Society of Cardiology (ESC), the European Atherosclerosis Society (EAS) and the European Society of Hypertension (ESH) in 1994. The main objective of the EUROASPIRE study (European Action on Secondary Prevention by Intervention to Reduce Events) was to evaluate to what degree the new recommendations have been implemented and whether a significant risk factor reduction in patients who presented with CHD has been achieved. The present study was conducted in the region of Münster, Westphalia, Germany, as part of the nine-country EUROASPIRE study.

METHODS

A total of 524 patients (58.6 +/- 8.2 years) were included in the study by abstracting data from their medical records. According to the clinical event which led to admission to the hospital, patients belonged to the following four groups: 1) coronary artery bypass graft (CABG), 2) percutaneous transluminal coronary angioplasty (PTCA), 3) acute myocardial infarction, 4) acute myocardial ischemia. Initially, a pre-specified number of patients had been recruited with the goal of having 100 patients in each of the four groups participate in the follow-up interview and examination. At least 6 months and, on average, 20 months after hospital discharge for the acute event, 74.8% of the patients came to an interview and examination for an evaluation of their risk profile.

RESULTS

At the interview, 15.6% of the patients smoked, 22.7% were obese, 54.6% had blood pressure levels above 140/90 mm Hg and 31.3% a total cholesterol/HDL-cholesterol-ratio greater than 5. Risk factor modification over time was insufficient as only one-fifth of patients had values of their risk factors within the target range at the time of the interview.

CONCLUSION

The goals of secondary prevention have not been achieved in the region of Münster-there is clearly room for improvement. Considering the treatment of patients with CHD, the recommended strategies of secondary prevention need to be applied more intensively in clinical practice.

[Acute thoracic aortic dissection with occlusion of the left coronary artery]

Aortic dissection is the most common fatal condition that involves the aorta. Occasionally, symptoms mimic acute myocardial infarction leading to thrombolytic treatment. Accurate diagnosis in patients with chest pain is therefore essential. We describe a case of acute aortic dissection which resulted in myocardial infarction due to obstruction of the left coronary ostium. A 65-year-old female patient with no previous cardiac history was admitted to a local hospital because of severe chest pain of acute onset. Physical examination was normal except for a low blood pressure (90/50 mm Hg), heart rate 45 beats/min and parasthesia in both hands. The ECG showed sinus bradycardia with negative T-wave in VI and with 1 mm ST-segment elevation in V3. A chest X-ray was normal. Five hours later, the patient experienced once more severe chest pain followed by non-sustained polymorphic ventricular tachycardia (Figure 1). Another ECG showed bifascicular bundle branch block (right bundle branch block and left anterior fascicular block). The ECG was interpreted as showing acute myocardial infarction and treatment with intravenous streptokinase started. Since the patient remained severely hypotensive despite infusion of dobutamine, she was intubated, ventilated and transferred to our hospital. Cardiac catheterization showed acute dissection of the ascending aorta with an aortic intimal flap and an occlusion of the left coronary artery (Figures 2a and b). During catheterization, she suffered a cardiac arrest from which she could not be resuscitated. A postmortem examination confirmed the acute aortic dissection which reached to the ostium of the left coronary artery (Figures 3a and b, 4a and b) and an anterior myocardial infarction probably due to intermitted diastolic obstruction of the ostium of the left coronary artery by an aortic intimal flap.

Coronary compliance in patients following orthotopic heart transplantation. An intravascular ultrasound study

BACKGROUND

The aim of this study was to investigate coronary compliance in patients early and 71.8 weeks after orthotopic heart transplantation.

METHODS

Thirty patients (mean age 51.4 years, women n = 6) underwent coronary angiography early after orthotopic heart transplantation (mean interval 11.6 +/- 5.5 weeks), by which time 12 recipients had already been treated for episodes of rejection. A total of 153 different coronary segments were investigated using a mechanical 30 MHz intravascular ultrasound system. In all segments, the intimal index and the circumferential extension of the vessel wall, which had a three-layered appearance, were assessed. Systolic-diastolic changes in area, and pressure with respect to vessel wall area, were used to study normalized compliance. All measurements were repeated in a subgroup of 13 patients 71.8 +/- 10.7 weeks after transplantation.

RESULTS

At the first investigation, the mean intimal index of all estimated cross-sectional areas was 0.07 +/- 0.10. The mean circumferential extension of the 'three-layered' coronary vessel wall was 74 degrees +/- 101 degrees. No correlation could be found between normalized compliance and the intimal index (r = -0.322, P < 0.001) or between normalized compliance and the circumferential extension of the three-layered vessel wall (r = -0.362, P < 0.001). Donor age did not correlate with normalized compliance either (r = -0.515, P = 0.004). In 12 patients with proven rejection periods before the first investigation, normalized compliance was significantly lower (1.76 +/- 0.81 mmHg-1) than in those without rejection (2.95 +/- 1.22 mmHg-1, P = 0.005). Both the intimal index and the circumferential extension of the three-layered architecture of the vessel wall were significantly higher in recipients with rejection periods. A comparison of the subgroup of 13 recipients between first and second investigation showed that the intimal index increased slightly from 0.03 +/- 0.03 to 0.09 +/- 0.13 (ns) 71.8 weeks after transplantation, but that normalized compliance did not differ significantly between the first and the follow-up investigation.

CONCLUSIONS

Early after orthotopic heart transplantation, normalized compliance does not correlate with donor age or the extent of atherosclerotic vessel alterations identifiable by intravascular ultrasound. Early rejection periods are associated with reduced coronary arterial compliance. Using intravascular ultrasound, this adverse functional effect on arterial compliance can be observed together with an increase in the intimal index.

Can Tl-201 myocardial SPECT abnormalities in orthotopic heart recipients be explained by coronary vessel wall alterations assessed by intravascular ultrasound?

The aim of this study was to compare findings on coronary intravascular ultrasound and thallium-201 SPECT in patients following orthotopic heart transplantation.

BACKGROUND

No data are available on whether pathological thallium scintigraphic findings in heart recipients are based on coronary vessel wall alterations identifiable by intravascular ultrasound.

METHODS

29 patients (mean age: 50.9 +/- 11.5 years; male n = 23) were investigated by means of intravascular ultrasound of selected coronary segments and thallium-201 myocardial SPECT. Patients were investigated 11.6 +/- 5.4 weeks post transplantation, a subgroup of 13 patients was re-investigated 70.2 +/- 18.4 weeks following transplantation. A total of 214 cross-sectional areas of the left coronary artery were examined using a 3.5 French intravascular ultrasound catheter to measure intimal index and the circumferential extension of a three-layer appearance of the vessel wall. Shortly after catheterisation, an ergometric stress-test was performed to examine all recipients by means of thallium-201 SPECT. In each patient, 20 segments of the left ventricle were evaluated using a score system of differentiate between persistent defects, redistribution, and reverse redistribution. A score was developed that measured the degree of inhomogeneity and severity of perfusion defects, respectively. Findings on scintigraphy were correlated to coronary intravascular ultrasound findings.

RESULTS

At first investigation, mean intimal index of all evaluated coronary cross-sectional areas was 0.06 +/- 0.1. Sixty-four cross-sectional areas demonstrated a three-layer appearance of the vessel wall, mean circumferential extension was 72 +/- 122 degrees. Thallium scintigraphy demonstrated a total of 336 (40%) pathological left ventricular segments; 168 (20%) were regarded as permanent defects, 67 (8%) demonstrated redistribution and 101 (12%) showed reverse redistribution. The score of inhomogeneity was calculated as 5.8% +/- 2.6%. In the subgroup of patients at the follow-up study, the score was 6.4 +/- 2.8%. There was no correlation between intimal index and the score, nor could any correlation be confirmed between the score and the circumferential extension of a three-layer appearance of the vessel wall. At second investigation, no significant differences of intimal index (0.05 +/- 0.07) or circumferential extension of a three-layer appearance of the vessel wall (74 +/- 118 degrees) could be confirmed. The score was slightly, but significantly increased to 8.1 +/- 4.5% at the second investigation (P < 0.05).

CONCLUSION

Early after orthotopic heart transplantation, pathologic thallium distribution patterns of the left ventricle could be observed. These pathological patterns did not correlate with the extent of diffuse coronary vessel wall alterations identifiable by intravascular ultrasound. After more than 1 year, the degree of scintigraphic abnormalities increased significantly, not accompanied by an increase of diffuse coronary vessel wall alterations.

[Intravascular sonographic findings after orthotopic heart transplantation: comparison with clinical factors]

30 patients (mean age 51.4 +/- 11.6 years; female n = 6) were studied early after orthotopic heart transplantation (11.6 +/- 5.5 weeks). Twelve recipients had undergone specific treatment for biopsy proven rejection. Using a mechanical intravascular ultrasound device (3.5-F catheter), 153 coronary artery segments (16 left coronary main stem, 122 left anterior descending artery, 15 left circumflex artery) were studied. Intimal index and circumferential extension of a three-layer appearance of the vessel wall were assessed. In all segments, systolic-diastolic changes in area (delta A) with respect to vessel area and pressure (delta P) were used to study normalized compliance (normalized compliance = [delta A/A]/delta P [mm Hg-1 x 10(3)]). Intravascular ultrasound findings were correlated to perioperative ischemia time, LDL/HDL-ratio, Lp(a) and donor age. In a subgroup of 13 recipients, intravascular ultrasound investigation was repeated after an interval of 67.4 +/- 10.2 weeks. At first investigation, mean intimal index of all coronary segments was 0.07 +/- 0.10. Mean circumferential extension of a three-layer appearance of the vessel wall was 84 +/- 112 degrees. Normalized compliance was 2.43 +/- 1.90 mm Hg-1 in the left main stem 2.45 +/- 1.47 mm Hg-1 within the left anterior descending artery, and 2.66 +/- 1.72 mm Hg-1 within the circumflex artery (differences n.s.). No correlation was found between intimal index and normalized compliance (r = -0.322), nor between circumferential extension of intimal thickening and normalized compliance (r = -0.362). Furthermore, there was no correlation between normalized compliance and donor age. Normalized compliance was significantly lower in recipients with proven rejection than in those without (1.76 +/- 0.81 versus 2.95 +/- 1.22 mm Hg-1, p = 0.005). Both, intimal index and circumferential extension of intimal thickening, were significantly higher in recipients following rejection periods (p < 0.05). The extent of coronary vessel wall alterations on ultrasound correlated to donor age but not to perioperative ischemia time, LDL/HDL-ratio and Lp(a). Re-investigation of a subgroup of 13 recipients 67.4 +/- 10.2 weeks after the first study showed an insignificant increase of the intimal index (from 0.03 to 0.09) and of the circumferential extension of intimal thickening (from 40 to 111 degrees). Normalized compliance changed from 2.53 +/- 1.48 to 2.87 +/- 1.33 mm Hg-1 (differences n.s.). Early after orthotopic heart transplantation, a significant correlation between atherosclerotic coronary vessel wall alterations assessed by intravascular ultrasound and donor age can be confirmed. Heart recipients following rejection periods present with significantly more atherosclerotic vessel wall alterations and a severely reduced compliance of the coronary vessels.

Isochromosome Xq in Klinefelter syndrome: report of 7 new cases

In this collaborative study we report on 2 prenatally and 5 postnatally diagnosed cases with a 47,X,i(Xq),Y chromosomal constitution. Excepting tall stature, the 5 adult patients showed all typical manifestations of Klinefelter syndrome. Taken together with previously reported cases, these data suggest that Klinefelter syndrome with isochromosome Xq has a favorable prognosis with normal mental development, and with normal-to-short stature. The prevalence of this Klinefelter variant is calculated to be between 0.3-0.9% in males with X chromosome polysomies.

Multiple cardiac procedures after heart transplantation: a case report

We report on a 56-year-old patient who underwent coronary artery bypass grafting, tricuspid valve replacement, and pacemaker implantation within 49 months after heart transplantation. This case readily demonstrates that multiple cardiac procedures can be safely performed after heart transplantation and may thus serve as an alternative to retransplantation.

Beating heart implantation of a wearable NOVACOR left-ventricular assist device

Implantable left-ventricular assist devices (LVAD) are successfully used as a bridge to transplant if the patient's condition is worsening and no donor organ is available. They allow recovery of compromised organ function. However, postoperative bleeding, thrombemboelism, and right-heart failure may jeopardize the important improvement of organ function and may even lead to death. We introduce our strategy for implantation of the Novacor LVAD system, which aims at minimal bleeding and maintained right-heart function. The Novacor LVAD was implanted with the heart beating during extracorporeal circulation in 8 patients, 3 of whom had previous cardiac surgery. Postoperatively, no patient developed right heart failure or had to undergo redo thoracotomy.