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C A Nienaber

Publications and source records attributed to C A Nienaber.

At least 19 recordsLinked to original sources
PubMed2007

[The "broken heart" syndrome--a rare clinical phenomenon].

BACKGROUND AND OBJECTIVE: A clinical entity that mimics acute coronary syndrome with reversible left ventricular systolic dysfunction and is triggered by emotional stress was identified in 6 patients by screening a database of > 1000 patients with the ICD-10 coding of acute coronary syndrome. The search criteria were acute coronary syndrome, normal coronary anatomy, absence of coronary lesions and transient left ventricular dysfunction, triggered by emotional stress. PATIENTS AND METHODS: We analyzed 6 patients, who fulfilled the criteria of (1) acute substernal chest pain with ST-segment elevation and/or T-wave inversion; (2) absence of significant coronary arterial narrowing on angiography, (3) systolic dysfunction with abnormal regional wall motion ("apical ballooning") in the context of (4) severe psychological stress immediately before and triggering the cardiac events. RESULTS: The primary diagnosis for all 6 acutely ill patients accorded with the ICD-code of acute coronary syndrome. All patients had survived and eventually recovered with an LV ejection fraction of 60 +/- 5 %; P = 0.03 and had had recovered normal levels of physical activity at hospital discharge. Of note is the number of women of postmenopausal age. CONCLUSIONS: A transient cardiomyopathy triggered by major emotional stress may mimic an acute coronary syndrome but without significant coronary artery disease. This condition is characterized by reversible cardiac dysfunction and may be more frequent in women. It has a favorable clinical outcome.

Acute Disease↗
PubMed2007

[The diagnostic dilemma of acute thoracic pain].

Acute aortic dissection is gaining recognition in Western societies, and is being diagnosed with increasing frequency. New diagnostic imaging modalities, longer life expectancy in general, as well as the increase in the number of hypertension patients have all contributed to the growing awareness of aortic dissections. Compared with acute coronary syndrome and lung embolism, aortic dissection is among the most frequently diagnosed life-threatening conditions involving chest pain. Here we report the case of a 59 year old patient suffering from hypertension and discuss the latest diagnostic and therapeutic procedures in the setting of acute chest pain.

Acute Coronary Syndrome↗
PubMed2006

[Hematothorax after sudden chest pain].

HISTORY: A 75-year-old woman was admitted to hospital because of the sudden onset of acute chest pain and dyspnea after defecation. INVESTIGATIONS: The initial working diagnosis was pulmonary embolism because of the clinical findings, laboratory results of elevated fibrin breakdown products and abnormal lung scintigraphy. However, persistent hemorrhagic pleural effusion on contrast enhanced computed tomography and magnetic resonance imaging subsequently revealed imminent rupture of the aorta from penetrating ulceration of the aorta with surrounding intramural hematoma. TREATMENT AND COURSE: Immediate implantation of an aortic stent-graft stopped leakage from the aorta and stabilized the patient's hemodynamic state. At follow up three months later the patient was without thoracic or cardiac symptoms. CONCLUSION: After exclusion of an acute coronary syndrome computed tomography imaging should always be performed in case of acute chest pain with no established cause. Interventional stent-graft placement can be an efficacious treatment option for emergency repair of imminent rupture in the descending aorta.

Acute Disease↗
PubMed2006

[Dual antithrombotic therapy after implantation of coronary stents].

Dual antiplatelet-aggregation treatment with aspirin and clopidogrel after coronary stent implantation is nowadays standard peri-interventional practice, although its use is not yet licensed for this indication in many European countries. Clopidogrel administration is initiated before PCI with a loading dose of 300 mg when given at least 6 hours before PCI, otherwise 600 mg. The required duration of combined (aspirin + clopidogrel) antiplatelet-aggregation treatment after coronary stent implantation depends on the type of stent and the pre-existing disease. After bare-metal stent implantation dual antiplatelet medication is needed for at least 3-4 weeks, after drug-eluting stent implantation 6 months, after coronary brachytherapy 12 months, and 9 months after an acute coronary syndrome. These time intervals should also be respected before any elective surgical intervention. Early operations, because postponement is impossible, should be performed under antiplatelet-aggregation treatment after assessment of bleeding risk in the individual case. Premature termination of this treatment carries an increased risk of serious cardiovascular events, especially stent thrombosis and myocardial infarction. Prolonged antiplatelet-aggregation treatment is of benefit especially in patients with a high risk of serious cardiovascular events. Patients with an indication for long-term anticoagulation may require, during the period of highest risk of stent thrombosis after stent implantation, administration of combined aspirin, clopidogrel and anticoagulants with an INR target value in the lower therapeutic range. The increased risk of bleeding must be weighed up against the potential benefit.

Aspirin↗
PubMed2006

[Stent-graft implantation in the thoracic aorta. Results of an interdisciplinary survey in Germany].

BACKGROUND AND OBJECTIVE: Endovascular stent-graft placement is emerging as a novel therapeutic option in patients with disease of the descending thoracic aorta. Quality standards for performing stent-graft procedures as well as for pre- and postoperative patient management are lacking, so far. It was the aim of this present survey to assess the current therapeutic standard of thoracic aortic stent-graft placement in Germany. METHODS: In a nationwide survey, a total of 206 vascular surgical, radiologic, cardiologic, and cardiothoracic surgical departments were contacted. Data concerning preoperative procedure planning, logistics, practical/technical issues of stent-graft placement, and postoperative patient management were evaluated using a standardized questionnaire comprising 29 items. Data analysis was performed using univariate analysis. RESULTS: 184 (89.3 %) of the 206 departments participated in the survey. Of these, 71 centers reported intending to perform or having performed thoracic aortic stent-graft placement. The survey overall represents 2267 endovascular stent-graft procedures performed in Germany between 1997/98 and 2003. On average, 7.4 stent-graft procedures/year were performed by each center, with half the centers performing fewer than 5 procedures/year. Thoracic aortic aneurysms was the main indication for endovascular stent-graft placement, followed by aortic dissection. There were significant differences between the different medical specialties which perform stent-graft procedures with respect to indications, choice of preoperative and intraoperative imaging methods, and technical equipment. There was strong agreement between the different centers concerning the necessity of a life-long follow-up after stent-graft placement, with computed tomography being the preferred imaging technique (90 % of centers). CONCLUSION: The present survey documents an increasing use of endovascular stent-graft placement in patients with disease of the descending thoracic aorta. There were differences regarding the technical execution of this procedures between specialties with respect to indication, procedure planning, and practical-technical aspects of stent-graft placement.

Analysis of Variance↗
PubMed2006

[Paraplegia after acute thoracic pain].

Severe neurological complications such as spinal cord ischemia and paraplegia can occur with acute aortic dissection in 3%. This report describes the case of a 67-year old patient with delayed onset of paraplegia 8 h after acute chest pain. Contrast enhanced computed tomography documented Stanford type B dissection confined to a short segment of the aorta. Furthermore, magnetic resonance imaging revealed intraspinal intraaxial hematoma of the myelon, which can explain the neurological complication. This case shows that even in the scenario of acute aortic dissection other mechanisms for paraplegia may be operational than dissection itself. Paraplegia in this case results from intramyelon bleeding preceding aortic dissection.

Acute Disease↗
PubMed2006

[Feasibility and safety of long-term AAI(R) pacing in isolated sinus node syndrome].

Recent investigations prove that AAI(R) pacing is the "ideal" stimulation mode in isolated sick sinus syndrome. Nevertheless, in Germany this bradycardia is treated by AAI(R) pacemakers in less than 4% of cases compared to 25% in other countries. In our institution treatment of patients with isolated sick sinus syndrome is uniform and corresponds to the actual guidelines since the early 1990s; therefore the aim of our study was to analyze feasibility and safety of AAI(R) pacing in a retrospective study. Between 1998 and 2000, 52 of 165 patients (31.5%) with isolated sick sinus syndrome were treated by an AAI(R) pacemaker. The median follow-up duration was 51.5 months (minimal: 36 months). 6 patients died, in all cases unrelated to the stimulation mode. Three patients required reoperations, however, in only one case due to second degree AV block with the need for upgrading to DDD stimulation. Thus, the yearly incidence of this specific complication in the AAI(R) cohort is 0.64%.In conclusion, permanent atrial stimulation in isolated sick sinus syndrome is feasible in a quarter of all cases. It is safe if performed corresponding to actual guidelines. Additionally, single lead AAI(R) pacing is a cost-effective therapy and the only stimulation mode which, today, reliably prevents unnecessary right ventricular stimulation. If, on the other hand, algorithms providing automatic mode switching from AAI to DDD and vice versa are implemented reliably into all dual chamber pacemakers, single chamber atrial pacing will no longer be a subject for discussion.

Aged↗
PubMed2006

[Left ventricular electromechanical latency period is an additional indicator to upgrade from right to biventricular DDD pacing].

In DDD pacing, the left-ventricular electromechanical latency period defines the duration between premature ventricular stimulation and the prematurely ending left-atrial contribution to left-ventricular filling. It has to be considered in diastolic AV delay optimization. Individual duration of this parameter seemed to reflect the ventricular function. Therefore, we compared the left-ventricular electromechanical latency period due to right ventricular stimulus with the documented ejection fraction of two groups, 33 congestive heart failure patients carrying biventricular systems and 13 right ventricular paced bradycardia patients. A mean latency period of 168+/-26 ms was found in the heart failure patients (ejection fraction: 25+/-5%) which was significantly longer (p=0.0039) compared to the bradycardia patients (ejection fraction: 51+/-12%) with a mean latency of 119+/-13 ms. Thus, an increasing latency period during right ventricular DDD pacing therapy indicates decreasing ejection fraction. A cut-off interval of 135 ms allowed the discrimination of 93% of our patients as having an individual ejection fraction of either up to 35% or above. Thus, the left ventricular electromechanical latency period can be used as an additional parameter indicating the necessity to upgrade from right to biventricular DDD pacing.

Bradycardia↗
PubMed2006

Percutaneous transcatheter closure of patent foramen ovale.

In presence of a patent foramen ovale (PFO) with cryptogenic cerebral embolism, traditional therapy consists of oral anticoagulation or antiplatelet therapy. Surgery was considered only in case of recurrence. Transcatheter closure of PFO is currently performed. The availability of new user friendly devices and the increasing knowledge of pathophysiology, epidemiology, and follow-up of these patients has broadened the indications and marked reduced morbidity related to interventional PFO closure. This review presents the current knowledge and our own data concerning transcatheter closure of PFO.

Cardiac Catheterization↗
PubMed2006

Interventional strategies for treatment of aortic dissection.

Endovascular treatment of chronic aneurysmatic diseases of the thoracic aorta has demonstrated encouraging peri-interventional mortality and morbidity and is accepted as a preferred strategy. The emerging of endovascular strategies for acute thoracic aortic dissection is an even more exciting new territory for nonsurgical interventions considering the sobering results of open surgery. Although it is apparent that patients at high risk for open surgery will benefit from endovascular strategies, the exact role of stent-graft placement remains to be defined at present as the community awaits solid long-term data and as devices and techniques continue to improve. While some indications and scenarios such as acute type B dissection with associated malperfusion syndrome or imminent aortic rupture have shown to benefit from stent-graft treatment, others are less settled. The current paper discusses both the established and emerging indications, as well as all technical aspects of this fascinating new therapeutic alternative. Moreover, the currently available data from small studies and registries are commented and analysed. Based on the available information the cardiovascular community is in the early phase of integrating a new rapidly evolving interventional concept into the care of patients with type B aortic dissection that so far lacked a reasonable therapeutic option other than blood pressure lowering medication. With the use and interpretation of current information the reader will understand the potential of interventional stent-graft induced thoracic aortic repair in type B aortic dissection.

Aortic Dissection↗
PubMed2005

[Contrast-media-induced nephrotoxicity].

The use of diagnostic and therapeutic catheterization is increasing and so is the exposure to radiocontrast media. As a consequence, an increasing incidence of contrast media-associated nephropathy is being observed. This article reviews pathogenesis, clinical symptoms and preventive measures of contrast media-associated nephropathy. Most important prophylactic measures is identification of high-risk patients, careful selection to be exposed to contrast media, application of non-ionic low osmolality or -- most recently -- iso-osmolality contrast media, adjusted hydration with isotonic saline before/during catheter interventions, and potentially the administration of acetylcysteine.

Contrast Media↗
PubMed2005

Sirolimus-eluting stent treatment for isolated proximal left anterior descending artery stenoses. Results from the prospective multi-center German Cypher Registry.

BACKGROUND: Stenting of isolated proximal LAD stenoses is still a controversial issue since it is associated with higher target vessel revascularization (TVR) rate than both bypass surgery using the internal mammary artery, and stenting of other coronary artery territories. The sirolimus- eluting stent (SES) has been reported to significantly reduce restenosis rates in de novo coronary lesions. Therefore, we compared patients from the German Cypher Registry treated with SES for isolated proximal LAD lesions with those stented for isolated lesions in the proximal LCX or RCA. METHODS: A total of 349 patients treated with SES were analyzed. 249 patients were treated for proximal LAD stenosis, and 100 for proximal LCX/RCA stenoses. The combined clinical endpoint was MACCE (death of any cause, non-fatal MI and non-fatal stroke) and TVR at 6 months. RESULTS: In-hospital events (death, MI and TVR) did not differ significantly between both groups (3.2% for the LAD group vs 2.0% for the LCX/RCA-group, p=0.73). The combined end point of death of any cause, non-fatal MI and non-fatal stroke at six months was 2.6% in the LAD group, and 2.2% in the LCX/RCA group (p=1.0). TVR occurred in 4.8% of the LAD group and in 6.5% of the LCX/RCA group at six months (p=0.58). The percentage of patients free from angina at daily activities was 80.6% in the LAD group, and 77.4% in the LCX/ RCA group (p=0.52). CONCLUSION: SES once implanted into isolated proximal LAD stenoses appears as effective as reported in other vessel territories. Accordingly, stenting of the proximal LAD using SES might prove a suitable alternative to surgery.

Activities of Daily Living↗
PubMed2005

[Interventional therapy of acute ST-elevation myocardial infarction in a regional network].

BACKGROUND AND OBJECTIVES: Management of acute ST-elevation myocardial infarction (STEMI) demands rapid and complete reflow to the infarct related artery (IRA). Primary PCI (percutaneous coronary intervention) performed by experienced operators is superior to thrombolytic thrombolytic therapy and reduces mortality, occurrence of non-fatal reinfarction and stroke, but is not available in rural Germany. We established a regional infarction-network using established therapeutic guidelines comprising of 1 interventional center and 7 referring community hospitals without PCI facilities. PATIENTS AND METHODS: We analyzed 322 patients with STEMI treated by PCI within the network; 160 patients were transferred from a community hospital without PCI facilities (transfer group (TG): 63.4 yrs., 71.8% men) and 162 patients were admitted directly to the interventional center (center group (CG): 61.7 yrs., 73.8% men). The interval from onset of symptoms to first medical contact was 205 minutes in TG, and 195 minutes in CG (n.s.); 7.8% of the CG and 7.2% of the TG patients were in cardiogenic shock; 95% of patients completed 12- months of follow-up. RESULTS: In the TG, median transportation time to PCI was 54 minutes. PCI of the infarct-related artery (IRA) was performed in 95.1% of TG patients and in 94.1% of CG patients. In addition, 96% of all patients received a GP IIb/IIIa receptor inhibitor. In case of pre-interventional application of GP IIb/IIIa receptor inhibitor 22.3% of patients revealed TIMI-3 flow of the IRA before PCI. After PCI, normalized flow to the IRAwas documented in 87.5% of CG versus 86.3% of TG. There were no differences between groups with respect to infarct size (TG vs. CG: CK 2482 vs. 2481 U/I; CKMB 302 vs. 264 U/I), mortality (30 days: 5.3 vs. 5.2%, 6 months: 7.3 vs. 7.1%, 12 months: 7.9 vs. 7.8%); NYHA (1.41 vs. 1.43) and left ventricular ejection fraction (0.41 vs. 0.43). CONCLUSIONS: The organization of a regional STEMI-network with logistic alliance of community hospitals and one experienced interventional center ensures timely PCI treatment of patients with STEMI according to present guidelines even in rural areas, and relegates thrombolytic treatment to bail-out scenarios only.

Aged↗
PubMed2004

[Guideline-conforming interventional treatment of acute ST-segment elevation myocardial infarction in rural areas using network collaboration].

BACKGROUND AND OBJECTIVES: Therapy of acute myocardial infarction demands rapid and complete myocardial reperfusion. Primary percutaneous coronary intervention (PCI) performed is superior to thrombolytic therapy in reducing mortality, non-fatal reinfarction and stroke, but is not available in rural Germany. PATIENTS AND METHODS: : From 8/2001 to 12/2002 322 patients with STEMI were treated by PCI with standardized therapeutic guidelines within a regional infarction-network comprising one interventional centre and 7 community hospitals without PCI facilities. 160 patients were relocated (transferred) from a community hospital without PCI facilities (transfer group, 63.4 yrs., 71.8 % men); 162 patients were admitted directly to the interventional centre (centre group, 61.7 yrs., 73.8 % men). The interval from onset of symptoms to first medical contact was 205 minutes in the transfer group, and 195 minutes in the centre group. 7.8 % of the centre group and 7.2 % of the transfer group patients were in cardiogenic shock. 95 % of patients have completed a 6-month's follow-up. RESULTS: In the transfer group median transportation time to PCI was 54 minutes. PCI of the infarct-related artery (IRA) was performed in 95.1 % of transferred patients after transfer and in 94.1 % of patients with direct admission. In addition 96 % of all patients received a GP IIb/IIIa receptor inhibitor. In case of pre-interventional application of the GP IIb/IIIa receptor inhibitor 22.3 % of patients revealed normal (TIMI-3) flow of the IRA before PCI, compared to 14.9 % TIMI-3 flow with 5000 IE Heparin/500 mg aspirin alone (p < 0.05). After PCI normalized flow in the IRA was documented in 87.5 % after direct admission and 86.3 % after transfer. No differences between groups were shown with respect to infarct size (transfer vs. centre: CK 2482 vs. 2481 U/I; CKMB 302 vs. 264 U/I), mortality (30 days: 5.3 vs. 5.2 %, 6 months: 7.3 vs. 7.1 %); NYHA (1.41 vs. 1.43) and left ventricular ejection fraction (0.41 vs. 0.43). CONCLUSIONS: The organization of a regional infarction-network with logistic alliance of community hospitals with one experienced interventional centre ensures timely PCI for patients with STEMI according to present guidelines even in rural areas.

Angioplasty, Balloon, Coronary↗
PubMed2004

"Real life" use of sirolimus-eluting coronary stents in Germany. Results from the prospective multi-centre German Cypher Registry.

BACKGROUND: Drugeluting stents (DES) are currently judged to be a "break-through" technology for the prevention of restenosis after percutaneous coronary interventions (PCI). However, experience is limited to randomised controlled clinical trials (RCT) in selected lesions and the currently available DES are more expensive compared to conventional "bare" stents. Therefore, actual clinical practice may be very different to RCT. METHODS: We analysed the data of the German Cypher trade mark Registry, a nationwide registry which was initiated in parallel to the launch of the first DES, the Cypher trade mark sirolimus-eluting coronary stent, in April 2002. RESULTS: From April 2002 until March 2003, 1638 procedures at 88 hospitals were included in the German Cypher trade mark Registry. The mean inclusion rate per centre and month remained low (<3 procedures/month and participating hospital) during the whole inclusion period. Most patients presented with stable angina pectoris (45.8%); however, 6.4% of patients were treated for a non-ST elevation myocardial infarction, 10.3% of patients for ST elevation myocardial infarction and 1.7% in cardiogenic shock. In patients without ST elevation myocardial infarction, a de novo stenosis was treated in 68.4% of cases, a restenosis in 4.1%, and an in-stent restenosis in 25.5% of cases. Chronic total occlusions were treated in 6.1% of patients. Predilatation was performed in 68.3% of patients and 1.05 +/- 0.35 Cypher trade mark stents were implanted per patient with a median (quartiles) stent length of 18 (13-21) mm. PCI-related death occurred in 0.1% of patients and a Q-wave myocardial infarction in 1.1%. Urgent re-PCI before hospital discharge was performed in 1.3% and urgent bypass surgery in 0.1% of cases. CONCLUSIONS: The use of the sirolimus-eluting coronary stents in this "real life" registry was found to be safe concerning acute complications. In about one half of the registry patients, the DES was implanted in lesions that were excluded from RCTs.

Blood Vessel Prosthesis↗