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Christian Lund

Publications and source records attributed to Christian Lund.

7 recordsLinked to original sources

Cerebral emboli during left heart catheterization may cause acute brain injury.

AIMS: Left heart catheterization carries a risk for cerebral complications. The aims of this prospective study were to determine the frequency and composition of catheterization-related cerebral microemboli and to detect cerebral morphological changes and acute cognitive impairment due to catheterization. METHODS AND RESULTS: Forty-seven unselected patients undergoing elective left heart catheterization, either by transradial or by transfemoral access, were monitored for cerebral microemboli using multifrequency transcranial Doppler. Cerebral magnetic resonance imaging (MRI) with diffusion-weighted imaging sequences and neuropsychological assessments were carried out on the day before and the day after catheterization. A median number of 754 cerebral microemboli were detected: 92.1% were gaseous and 7.9% were solid. New cerebral lesions were observed in 15.2% of the transradial, but none of the transfemoral, catheterization patients (P=0.567). These lesions were significantly associated with a higher number of solid microemboli (P=0.016) and a longer fluoroscopy time (P=0.039). There was also a significantly higher number of solid microemboli during transradial than during transfemoral catheterization (P=0.012). Cognitive impairment following the investigations was associated with the degree of pre-catheterization cerebral MRI injury (P=0.03). CONCLUSION: During left heart catheterization, cerebral microemboli, especially those which are solid, may damage the brain. Cardiac catheterization may therefore pose a greater risk for the brain than previously acknowledged.

Aged↗

Cerebral ischemic injury and cognitive impairment after off-pump and on-pump coronary artery bypass grafting surgery.

BACKGROUND: Off-pump coronary artery bypass grafting surgery reduces the intraoperative cerebral embolic load and may therefore cause less brain injury. The main aim of this study was to compare off-pump and on-pump surgery with regard to the frequency of new postoperative cerebral ischemic lesions and the prevalence of postoperative cognitive impairment. We also assessed whether preoperative cerebral ischemic injury predicts the risk for cognitive dysfunction after surgery. METHODS: One hundred twenty patients with ischemic coronary artery disease were prospectively randomized to undergo off-pump or on-pump surgery. A detailed neuropsychological assessment and a cerebral magnetic resonance imaging examination were performed on the day before and at 3 months postoperatively. The neuropsychological assessment was repeated at 12 months. RESULTS: There was no significant (p = 0.17) difference between off-pump (8.2%) and on-pump (17.3%) surgery with regard to new postoperative cerebral lesions. The prevalence of cognitive impairment after surgery was also similar in the two groups (3 months: off-pump 20.4%, on-pump 23.1%, p = 0.74; 12 months: off-pump 24.1%, on-pump 23.1%, p = 0.90). The degree of preoperative cerebral ischemic injury was significantly associated with cognitive dysfunction after on-pump (p = 0.02) but not after off-pump (p = 0.22) surgery. None of the patients with normal preoperative radiologic findings were found to have cognitive impairment at 3 months postoperatively (p = 0.04). CONCLUSIONS: Long-term cognitive function and magnetic resonance imaging evidence of brain injury were similar after off-pump and on-pump coronary artery bypass grafting surgery. Preoperative cerebral magnetic resonance imaging can be used to predict the risk for cognitive dysfunction after coronary artery bypass grafting surgery.

Adult↗

Preoperative cerebral ischemic lesions predict physical health status after on-pump coronary artery bypass surgery.

BACKGROUND: Risk assessment is integral to patient selection and counseling before coronary artery revascularization. We studied the predictive ability of cerebral magnetic resonance imaging of preoperative and postoperative cerebral ischemic injury on self-reported physical and mental health at 3 months after coronary artery bypass surgery with or without use of cardiopulmonary bypass. METHODS: In a prospective clinical trial comparing on-pump and off-pump surgery, 120 patients responded to a questionnaire for self-report of angina (Canadian Cardiovascular Society scale) and physical and mental health status (Short Form 36) at baseline before preoperative cerebral magnetic resonance imaging. Preoperative sets of both magnetic resonance imaging and self-assessments were available for 103 (85.8%) patients. These patients were grouped according to classification of preoperative cerebral magnetic resonance imaging findings. Analysis of covariance determined the association of (1) preoperative magnetic resonance imaging status, (2) new postoperative cerebral lesions, and (3) actual use of cardiopulmonary bypass to physical and mental health. RESULTS: At 3 months after surgical intervention, 98 of 103 patients completed follow-up. The analysis revealed an interaction effect of preoperative cerebral ischemic injury and use of cardiopulmonary bypass on physical health (F = 9.07, P = .003) independent of age. No independent effects on health status were found of baseline magnetic resonance imaging or new cerebral lesions at 3 months. CONCLUSIONS: This study strongly suggests that the combination of preoperative cerebral ischemic injury and use of cardiopulmonary bypass can predict postoperative health status at 3 months. Cerebral magnetic resonance imaging might be a more specific indicator than age for preoperative assessment of vulnerability or resilience during rehabilitation after on-pump cardiac surgery.

Adult↗

Endoscopic ultrasound, positron emission tomography, and computerized tomography for lung cancer.

Staging of patients with lung cancer to determine operability is intended to efficiently limit futile thoracotomies without denying possibly curative surgery. Currently available staging tests are imperfect alone and in combination. Imaged suspected metastases often require tissue confirmation before surgery can be denied. Endoscopic ultrasound (EUS) may help identify inoperable patients by providing tissue proof of inoperability in a single staging test, with similar sensitivity for identifying inoperable patients as other staging tests. Therefore, we compared computed tomography, positron emission tomography (PET), and EUS with fine-needle aspiration under conscious sedation, each test interpreted blinded with respect to the other tests, for identifying inoperable patients in a consecutive cohort of 79 potentially operable patients with suspected or proven lung cancer. An economic analysis was also performed. Thirty-nine patients were found inoperable (a 40th patient's inoperability was missed by all preoperative staging tests). The sensitivity of computerized tomography was 43%. PET and EUS each had similar sensitivities (68 and 63%, respectively) and similar negative predictive values (64 and 68%, respectively), but EUS's superior specificity (100 vs. 72% for PET) and considerably lower expense means it may be preferred to PET early in staging to identify inoperable patients.

Adult↗

Comparison of cerebral embolization during off-pump and on-pump coronary artery bypass surgery.

BACKGROUND: Coronary artery bypass surgery with cardiopulmonary bypass carries a significant risk of perioperative brain injury. At least 1% to 5% will suffer a stroke, and at 3-months postoperatively approximately 30% are reported to have cognitive impairment assessed by neuropsychologic testing. In off-pump surgery cardiopulmonary bypass is not used and instrumentation on the ascending aorta is reduced. The main aim of this study was to assess if off-pump surgery reduces intraoperative cerebral embolization. METHODS: This was a prospective and randomized study of two comparable groups with regard to age, sex, years of education, preoperative cognitive functioning, and surgical characteristics. Fifty-two patients (29 off-pump) were monitored by the use of transcranial Doppler ultrasound for cerebral microembolization during surgery. Preoperative and postoperative clinical, cerebral magnetic resonance imaging, and neuropsychologic examinations were also carried out. RESULTS: There was a significant reduction in the number of cerebral microemboli during off-pump compared with on-pump surgery (16.3 [range 0 to 131] versus 90.0 [range 15 to 274], p < 0.0001). No significant difference with regard to the incidence of neuropsychologic performance (decline in 29% off-pump, 35% on-pump) or neuroradiologic findings at 3 months was found, and there was no association between the number of cerebral microemboli and cognitive outcome. CONCLUSIONS: This study clearly demonstrates that off-pump surgery leads to a reduction in intraoperative cerebral microembolization. A significant reduction in the number of off-pump patients with cognitive decline or ischemic brain lesions on cerebral magnetic resonance imaging could not be demonstrated in this relatively small patient population.

Aged↗

Mediastinal lymph node involvement in potentially resectable lung cancer: comparison of CT, positron emission tomography, and endoscopic ultrasonography with and without fine-needle aspiration.

PURPOSE: A prospective comparison of three imaging techniques: thoracic CT, positron emission tomography (PET), and endoscopic ultrasonography (EUS) with fine needle aspiration (FNA), each performed under routine conditions, for the detection of metastatic lymph nodes metastases in patients with lung cancer considered for operative resection. PATIENTS AND METHODS: Following bronchoscopic evaluation, CT, PET, and EUS were performed to evaluate potential mediastinal involvement in 33 consecutive patients with bronchoscopic biopsy/cytology proven (n = 25) or radiologically suspected (n = 8) lung cancer prior to surgery. Surgical histology was used as "gold standard" to confirm the diagnosis of the primary tumor and the mediastinal status in all patients. Histology proved non-small cell lung cancer in 30 patients, neuroendocrine tumor in 1 patient, and benign disease in 2 patients. RESULTS: The mean age of the study group was 61.5 years (range, 41 to 80 years; 23 male patients). CT, PET, and EUS detected mediastinal lymph nodes (size, 0.4 to 1.6 cm) in 15, 14, and 27 patients (21 of which were suspected to be malignant on EUS), respectively. With respect to the correct prediction of mediastinal lymph node stage, the sensitivities of CT, PET, and EUS were 57%, 73%, and 94%. Specificities were 74%, 83%, and 71%. Accuracies were 67%, 79%, and 82%. Results of PET could be improved when combined with CT (sensitivity, 81%; specificity, 94%; accuracy, 88%). The specificity of EUS (71%) was improved to 100% by FNA cytology (EUS-guided FNA), which gave a tissue diagnosis including tumor type, without complications. CONCLUSIONS: No single imaging method alone was conclusive in evaluating potential mediastinal involvement in apparently operable lung cancer and routine clinical conditions. A tissue diagnosis is extremely helpful. Because FNA can be performed at the same time as EUS, this combination emerged as the most useful technique in the evaluation of even very small mediastinal metastases of lung cancer. CT seems necessary additionally to evaluate the pretracheal region as well as the rest of the thorax, and PET may be valuable to detect distant metastases.

Adult↗