Early results after mitral valvuloplasty for pure mitral regurgitation

In this study we present the results of 105 consecutive patientswith pure mitral regurgitation who underwent surgical treatment.In all patients mitral regurgitation was associated with mitralvalve prolapse: 54 patients underwent mitral valvuloplasty and51 patients mitral valve replacement. Clinical assessment and echocardiography were used as follow-upcriteria at one year after surgery. After mitral valvuloplasty,NYH A decreased from 2.7±0.8 to 1.1±0.7 (P<0.01)and workload capacity increased from 65±28% to 96±25%(P<0.001); left endsystolic atrial dimension and enddiastolicdimension decreased from 6.2±0.8 to 4.8±1.2 cm(P<0.001) and from 7.2±1.3 to 5.9±0.8 cm (P<0.01);ventricular contraction fraction did not change significantly. After mitral valve replacement, clinical and echocardiographicimprovement was significant but less remarkable than after valvuloplasty;ventricular contraction fraction fell from 39±7% to 29±8%in contrast to patients undergoing mitral valvuloplasty in whomno significant change occurred. Complications were rare in both groups though only a minorityof patients undergoing mitral valvuloplasty received anticoagulants.We conclude that mitral valvuloplasty in patients with puremitral regurgitation associated with mitral valve prolapse givesexcellent results, particularly regarding left ventricular functionwhen compared with the patients after mitral valve replacement.     

Infected Endocardial Pacemaker Electrodes: Successful Open Intracardiac Removal

The long-term results after open intracardiac removal of infected pacing electrodes are presented. Methods: between 1985 and 1990 open intracardiac removal of 19 infected pacing electrodes was performed in seven patients (six male and one femalel, with a mean age of 56 years. The indications were; persisting bacteremia in three; generator pocket infection in four; endocarditis in one; and ventricular tachycardia caused by retracted electrodes in one. All electrodes were fixed in the right heart and extraction by closed methods failed. Percutaneous catheter techniques were not applied in these seven patients. In five patients two ventricular electrodes had to be removed, and in two patients a single one. A total of seven atrial electrodes were removed in six patients (one electrode each in five patients; two electrodes in one patient). All atrial and two ventricular electrodes could be removed through a pursestring suture without use of a pump oxygenator. For the removal of ten ventricular electrodes in six patients (two electrodes each in four patients; 1 electrode each in two patients) a right-sided atriotomy was necessary with cardiopulmonary bypass (CPB). Simultaneously, five new pacing systems were implanted. Results; there were no early or late mortalities. In January 1991, all seven patients are alive and in a mean New York Heart Association Class 1,3 of heart failure after a mean interval of 33 months. In all cases the infection could be controlled with a simultaneous antimicrobial chemotherapy and the postoperative period was free of major complications. Conclusion; open intracardiac removal of retained pacing electrodes with or without use of CPB is a safe procedure without major complications. It is mandatory for all infected pacing electrodes that cannot be extracted by closed methods.     

Early results after mitral valvuloplasty for pure mitral regurgitation

In this study we present the results of 105 consecutive patientswith pure mitral regurgitation who underwent surgical treatment.In all patients mitral regurgitation was associated with mitralvalve prolapse: 54 patients underwent mitral valvuloplasty and51 patients mitral valve replacement. Clinical assessment and echocardiography were used as follow-upcriteria at one year after surgery. After mitral valvuloplasty,NYH A decreased from 2.7±0.8 to 1.1±0.7 (P<0.01)and workload capacity increased from 65±28% to 96±25%(P<0.001); left endsystolic atrial dimension and enddiastolicdimension decreased from 6.2±0.8 to 4.8±1.2 cm(P<0.001) and from 7.2±1.3 to 5.9±0.8 cm (P<0.01);ventricular contraction fraction did not change significantly. After mitral valve replacement, clinical and echocardiographicimprovement was significant but less remarkable than after valvuloplasty;ventricular contraction fraction fell from 39±7% to 29±8%in contrast to patients undergoing mitral valvuloplasty in whomno significant change occurred. Complications were rare in both groups though only a minorityof patients undergoing mitral valvuloplasty received anticoagulants.We conclude that mitral valvuloplasty in patients with puremitral regurgitation associated with mitral valve prolapse givesexcellent results, particularly regarding left ventricular functionwhen compared with the patients after mitral valve replacement.     

Predictability of aortic dissection as a function of aortic diameter

The role of aortic diameter on the occurrence of type A dissectionwas investigated in 73 patients with dilated ascending aortaat the lime of pre-operative evaluation. Using transthoracicechocardiography for diagnosis and measurements, 54 patientswere identified with type A dissection (group 1) and 19 withoutdissection (group 2). The true mean aortic diameters were identical(6·0±1·3 cm in group 1 and 6·4±1·4cm in group 2; mean±SD; ns) as were the indexed aorticdiameters (ratio of diameter/body surface area; 3·2±0·8cm . m^–12 and 3·4±0·7cm m^–2respectively; ns). However, the individual diameters showeda pronounced scatter in both groups (range from 3·6±11·0cm). Of the 73 patients, 66 had surgery (47/54 with and 19/19without dissection) and seven patients were treated medically.Emergency surgery was performed in 45/66 patients (all withacute type A dissection) andelective repair in 21/66 (19 withoutand two with chronic type A dissection). In-hospital mortalitywas 18% in the emergency group, 5% in the elective group and57% in the medical group. It is concluded that patients with dilated ascending aorta havea substantial incidence of acute dissection. Their clinicalcourse is unpredictable; acute dissection occurs in some, andin others the ascending aorta continues to enlarge without dissection.Because patients with dissection often arrive too late for electiverepair andhave to be operated on as emergencies with a higheroperative risk, we recommend elective surgery before the diameterof the ascending aorta has reached 6 cm.     

Autonomic Nervous System-Controlled Cardiac Pacing: A Comparison Between Intracardiac Impedance Signal and Muscle Sympathetic Nerve Activity

BINGGELI, C., et al. : Autonomic Nervous System‐Controlled Cardiac Pacing: A Comparison Between Intracardiac Impedance Signal and and Muscle Sympathetic Nerve Activity. A recently introduced rate responsive cardiac pacing system is based on information derived from the intracardiac impedance signal containing information on the inotropic state of the ventricle. This study compared the inotropic state index (ISI) with muscle sympathetic activity (MSA), both being modulated by the autonomic nervous system. Nine patients (66 ± 3 years, mean ± SEM ) with Inos2DR pacemakers were included. Each patient was studied at rest and during cold pressor test (CPT). Microneurography of the peroneal nerve was performed to measure MSA continuously, which was digitally stored along with continuous surface ECG and blood pressure. The intracardiac impedance signal was transmitted by the pacemaker and stored simultaneously. Linear correlation between ISI and MSA was calculated for the period of the CPT. During CPT, mean systolic blood pressure increased from 122 ± 4 to 149 ± 6 mmHg (P < 0.0001), diastolic blood pressure increased from 74 ± 8 to 86 ± 4 mmHg (P = 0.02 ), and intrinsic heart rate increased from 69 ± 7 to 75 ± 7 beats/mill (P = 0.019 ). ISI increased by 21 ± 7% (P = 0.018 ), MSA by 26 ± 6% (P = 0.004 ). ISI and MSA were positively correlated during the CPT in eight of nine patients (R2 = 0.86–0.99, P < 0.0001 ). Negative correlation was found in one patient (R2 = 0.94 ). This study demonstrates parallel increases of the ISI and MSA during CPT. ISI and MSA showed a close linear relationship during provoked changes of sympathetic activity. These results provide further evidence that the sympathetic nervous system is responsible for the observed ISI changes.     

EXPRESSION OF THE LAMININ γ2 CHAIN IN PANCREATIC ADENOCARCINOMA

Forty-two pancreatic adenocarcinomas were investigated immunohistochemically and by in situ hybridization for the expression of the laminin γ 2 chain. In 41 cases, intracytoplasmic immunoreactivity for the γ2 chain was seen. Positive tumour cells were located especially at the epithelial–stromal interface of the tumour cell islands. In 22 cases, diffuse laminin γ2 chain immunoreactivity could also be seen in stroma and in seven cases, occasional positivity was detected in the neoplastic basement membranes. Signals for laminin γ2 chain mRNA in tumour cells displayed a distribution similar to that observed on immunohistochemistry. There were significantly more cases with less than 20 per cent of laminin γ2 chain-positive tumour cells in tumours extending to peripancreatic tissues and/or tumours with regional or distant metastases ( P =0·029). A corresponding statistical significance could also be noted in the mRNA level ( P =0·025). The results show that pancreatic adenocarcinomas display a high activity of laminin γ 2 chain synthesis. Tumours with a strong laminin γ2 chain synthesis show a lower invasive and metastatic potential than tumours with a weak or moderate laminin γ2 chain expression.