Long-term follow-up after surgery for atrial fibrillation with concomitant open heart surgery. / Langtidsoppfølging etter atrieflimmeroperasjon og samtidig åpen hjertekirurgi.

BACKGROUND: Patients with atrial fibrillation and atrial flutter scheduled to undergo open heart surgery can receive ablation treatment of arrhythmogenic foci during the same intervention. Sinus rhythm is restored in the majority in the short term, but the long-term results are more uncertain. This study, which is part of the international CURE-AF trial, evaluates results after Cox-Maze IV surgery for atrial fibrillation in Norway at six-year follow-up. MATERIAL AND METHOD: Nineteen patients were included in this prospective cohort study. Atrial fibrillation had persisted for 40 months in the group with long-standing persistent atrial fibrillation (n = 12) and 6 months in the group with persistent atrial fibrillation (n = 7). Surgery for atrial fibrillation was performed according to the Cox-Maze IV procedure in the CURE-AF protocol. Follow-up in the first 12 months was strictly according to the CURE-AF protocol, thereafter conducted by the primary health service. RESULTS: Sinus rhythm was restored in 11 patients at the time of discharge and in 14 patients six months postoperatively. After 5-6 years of follow-up, all patients with long-standing persistent atrial fibrillation had experienced recurrence. Two achieved sinus rhythm after electroconversion. Six of the seven in the group with persistent atrial fibrillation had sinus rhythm after 5-6 years. INTERPRETATION: The results were good initially, with restoration of sinus rhythm in more than two thirds of the patients after 6-9 months. Five years later, a high recurrence rate was found in patients with long-standing persistent atrial fibrillation. Several recurrences had not been detected by the public health service or treatment had not been attempted.

Outcome After Rewarming From Accidental Hypothermia by Use of Extracorporeal Circulation.

BACKGROUND: Accidental hypothermia with arrested circulation remains a condition associated with high mortality. In our institution, extracorporeal circulation (ECC) rewarming has been the cornerstone in treating such patients since 1987. We here explore characteristics and outcomes of this treatment, to identify significant merits and challenges from 3 decades of experience in ECC rewarming. METHODS: Sixty-nine patients rewarmed by ECC during the period from December 1987 to December 2015 were analyzed. One patient was excluded from the analyses because of combined traumatic cerebral injury. The analysis was focused on patient characteristics, treatment procedures, and outcomes were focused. Survivors were evaluated according to the cerebral performance categories scale. Simple statistics with nonparametric tests and χ2 tests were used. Median value and range are reported. RESULTS: Median age was 30 years (minimum 1.5, maximum 76), and the cause of accidental hypothermia was cold exposure (27.9%), avalanche (5.9%), and immersion/submersion accidents (66.2%). Eighteen patients survived (26.5%). The survival rate did not improve during the years. Survivors had lower serum potassium (p = 0.002), higher pH (p = 0.03), lower core temperature (p = 0.02), and shorter cardiopulmonary resuscitation time (p = 0.001), but ranges were wide. Although suspected primary hypoxia and hypothermia were associated with lower survival, we observed a 10.5% survival of these victims. Sixteen survivors had good outcome (cerebral performance category 1 or 2), whereas 2 patients with suspected primary hypoxia survived with severe cerebral disability (cerebral performance category 3). CONCLUSIONS: Despite extended experience with ECC rewarming, improved handling strategies, and intensive care, no overall improvement in survival was observed. Good outcome was observed even among patients with a dismal prognosis.

Intraaortic counterpulsation during cardiopulmonary bypass impairs distal organ perfusion.

BACKGROUND: Recent studies have focused on the use of fixed-rate intraaortic balloon pumping (IABP) during cardiopulmonary bypass (CPB) to achieve pulsatile flow. Because application of an IABP catheter may represent a functional obstruction within the descending aorta, we explored the effect of IABP-pulsed CPB-perfusion with special attention to perfusion above and below the IABP balloon. METHODS: Sixteen animals received an IABP catheter that remained turned off position (NP group, n = 8) or was switched to an automatic mode of 80 beats/min during CPB (PP group, n = 8). Flow-data and pressure-data were obtained above and below the IABP balloon. Tissue perfusion was evaluated by microspheres. RESULTS: IABP-pulsed CPB-perfusion, as assessed at 30 minutes on CPB, increased proximal mean aortic pressure (p < 0.05) and carotid artery blood flow (p < 0.001), but decreased distal mean aortic pressure (p < 0.001). The decrease of distal mean aortic pressure in the PP group was associated with a 75 % decrease (p < 0.001) of renal tissue perfusion. During nonpulsed perfusion the respective variables remained essentially unchanged compared with pre-CPB levels. CONCLUSIONS: Using IABP as a surrogate to achieve pulsatile perfusion during CPB contributes significantly to lowered aortic pressure in the distal portion of aorta and impaired tissue perfusion of the kidneys. The results are focusing on effects that may contribute to organ dysfunction and acute kidney injury. Consequently, assessment of perfusion pressure distal to the balloon should be addressed whenever IABP is used during CPB.

Acute obstruction by Pannus in patients with aortic medtronic-hall valves: 30 years of experience.

BACKGROUND: Acute dysfunction of mechanical aortic valve prostheses is a life-threatening adverse event. Pannus overgrowth, which is fibroelastic hyperplasia originating from the periannular area, is one cause of dysfunction. The aim of this study was to determine the annual incidence of readmittance resulting from acute obstruction caused by pannus during 30 years of observation in patients with Medtronic-Hall aortic valve prostheses and to analyze the risk factors associated with pannus development. METHODS: From 1982 to 2004, 1,187 patients in our department underwent aortic valve replacement with Medtronic-Hall mechanical monoleaflet valve prostheses. As of December 31, 2012, 27 of these patients (2.3%) had presented with acute valve dysfunction caused by pannus obstruction. RESULTS: The annual incidence of pannus was 0.7 per 1,000. The median time from the primary operation to prosthetic dysfunction was 11.1 years (range, 1.2 to 26.8 years). Of the 20 patients who underwent reoperation, 2 died. Seven patients died before reoperation. Women had a higher risk for the development of obstructing pannus, and patients with pannus obstruction were younger. Valve size was not an independent risk factor. CONCLUSIONS: Women and younger patients are at higher risk for pannus development. When acute dysfunction by pannus is suspected in a mechanical aortic valve, an immediate echocardiogram and an emergency aortic valve replacement should be carried out because of the potential of a fatal outcome.

Microvascular fluid exchange during pulsatile cardiopulmonary bypass perfusion with the combined use of a nonpulsatile pump and intra-aortic balloon pump.

OBJECTIVE: To evaluate how pulsed versus nonpulsed cardiopulmonary bypass influences microvascular fluid exchange in an experimental setup combining a nonpulsatile perfusion pump and an intra-aortic balloon pump. METHODS: A total of 16 pigs were randomized to pulsatile cardiopulmonary bypass perfusion with an intra-aortic balloon pump switched to an automatic 80 beats/min mode after the start of cardiopulmonary bypass (pulsatile perfusion [PP] group, n = 8) or to nonpulsatile cardiopulmonary bypass with the pump switched to the off position (nonpulsatile [NP] group, n = 8). Normothermic cardiopulmonary bypass was initiated after 60 minutes of stabilization and continued for 3 hours. The fluid needs, plasma volume, colloid osmotic pressure in plasma, colloid osmotic pressure in interstitial fluid, hematocrit, and total tissue water content were recorded, and the protein masses and fluid extravasation rates were calculated. RESULTS: After cardiopulmonary bypass was started, the mean arterial pressure increased in the PP group and decreased in the NP group. At 180 minutes, the mean arterial pressure of the PP and NP groups was 70.9 ± 2.7 mm Hg and 55.9 ± 2.7 mm Hg, respectively (P = .004). The central venous pressure (right atrium) had decreased in the NP group (P = .002). A decreasing trend was seen in the PP group. No between-group differences were present. The hematocrit and colloid osmotic pressure in plasma and interstitial fluid had decreased similarly in both study groups during cardiopulmonary bypass. The plasma volume of the PP group had decreased initially but then returned gradually to precardiopulmonary bypass levels. In the NP group, the plasma volume remained contracted (P = .02). No significant differences in the fluid extravasation rate were obtained. The fluid extravasation rate of the PP group tended to stay slightly higher than the fluid extravasation rate of the NP group at all measurement intervals. The total tissue water content increased significantly in a number of organs compared with that in the control animals. However, differences in the total tissue water content between pulsed and nonpulsed perfusion were absent. CONCLUSIONS: No significant differences in the fluid extravasation rates were present between pulsed and nonpulsed cardiopulmonary bypass perfusion in the present experimental setup.

Incidental detection of internal jugular vein thrombosis secondary to undiagnosed benign substernal goiter.

Internal jugular vein thrombosis is a serious event with potentially fatal outcome, where the clinical symptoms may be vague or absent. This paper refers to a rare case where routine carotid Doppler ultrasound prior to coronary artery bypass grafting (CABG) and aortic valve replacement (AVR) in a 76-year-old man, incidentally revealed thrombosis of the right internal jugular vein. Thoracic CT demonstrated an underlying, large, benign substernal multinodular goiter, mainly involving the right lobe, causing compression and displacement of the great vessels. A successful, one-stage operation including ligation of the internal jugular vein to avoid pulmonary embolism and hemithyroidectomy, combined with the scheduled CABG and AVR, was performed. This case illustrates that benign substernal goiter may be associated with asymptomatic internal jugular vein thrombosis. Carotid Doppler ultrasound should involve evaluation of the internal jugular vein concerning thrombosis as its presence may reveal space-occupying lesions in the thorax.