Optimal patient selection for maze procedure in patients undergoing mitral valve disease

OBJECTIVES

Although risk factors for unsuccessful Maze procedure have been demonstrated, an appropriate patient selection is still controversial. In our institute, Maze procedure is indicated for those whom normal sinus rhythm (NSR) was reestablished by intraoperative direct cardioversion (DC) after ventricular unloading by total cardiopulmonary bypass. The purpose of this study was to evaluate the effectiveness of our indication criteria for Maze procedure in patients with mitral valve disease.

METHODS

Between October 2012 and October 2021, MAZE was indicated in 55 patients in whom normal sinus rhythm (NSR) was reestablished by intraoperative direct current cardioversion (DC). Three endpoints and predictors were examined: disappearance of atrial fibrillation (AF), NSR, and A-wave detection.

RESULTS

Restoration of NSR by intraoperative DC was confirmed in 43 patients, and these patients underwent MAZE. AF disappeared in 39 patients (90.7%), and F-wave ≥ 0.1 mV was a significant predictive factor (odds ratio (OR) 20.99, 95% CI 1.22-1079.06). NSR was reestablished in 36 patients (83.7%), and F-wave ≥ 0.1 mV (odds ratio 15.62, 95% CI 1.62-359.86) + AF history ≤ 3 years (OR 8.30, 95% CI 1.09-177.04) were significant predictors. A-wave detection was confirmed in 26 patients (60.5%), and left atrial diameter ≤ 55 mm was a significant predictor (OR 5.22, 95% CI 1.28-24.79).

CONCLUSIONS

Intraoperative DC after ventricular unloading resulted effective patient selection for concomitant Maze procedure. F-wave and AF history were predictive factor of electrical restoration of AF, and left atrial diameter was predictive factor of restoration of atrial function.

Potential confounders of the obesity paradox in older patients following transcatheter aortic valve replacement

PURPOSE

A higher body mass index (BMI) is associated with lower mortality in older patients following transcatheter aortic valve replacement (TAVR) for severe aortic valve stenosis. The current study aimed to investigate potential confounders of association between BMI and prognosis.

METHODS

The retrospective single-center study included consecutive patients following TAVR and excluded those in whom subcutaneous fat accumulation (SFA), visceral fat accumulation (VFA), and major psoas muscle (MPM) volume were not assessed by computed tomography. Cachexia was defined as a combination of BMI < 20 kg/m2 and any biochemical abnormalities.

RESULTS

After 2 patients were excluded, 234 (age, 86 ± 5 years; male, 77 [33%]; BMI, 22.4 ± 3.8 kg/m2; SFA, 109 (54-156) cm2; VFA, 71 (35-115) cm2; MPM, 202 (161-267) cm3; cachexia, 49 [21%]) were evaluated. SFA and VFA were strongly correlated with BMI (ρ = 0.734 and ρ = 0.712, respectively), whereas MPM was weakly correlated (ρ = 0.346). Two-year all-cause mortality was observed in 31 patients (13%). Higher BMI was associated with lower mortality (adjusted hazard ratio [aHR], 0.86; 95% confidence interval [CI], 0.77-0.95). A similar result was observed in the multivariate model including SFA (aHR in an increase of 20 cm2, 0.87; 95% CI, 0.77-0.98) instead of BMI, whereas VFA was not significant. Cachexia was a worse predictor (aHR, 2.51; 95% CI 1.11-5.65).

CONCLUSIONS

Association of higher BMI with lower mortality may be confounded by SFA in older patients following TAVR. Cachexia might reflect higher mortality in patients with lower BMI.

Clinical impact of the right ventricular impairment in patients following transcatheter aortic valve replacement

The right ventricular (RV) impairment can predict clinical adverse events in patients following transcatheter aortic valve replacement (TAVR) for severe aortic stenosis (AS). Limited reports have compared impact of the left ventricular (LV) and RV disorders. This retrospective study evaluated two-year major adverse cardiac and cerebrovascular events (MACCE) in patients following TAVR for severe AS. RV sphericity index was calculated as the ratio between RV mid-ventricular and longitudinal diameters during the end-diastolic phase. Of 239 patients, 2-year MACCE were observed in 34 (14%). LV ejection fraction was 58 ± 11%. Tricuspid annular plane systolic excursion (TAPSE) and RV sphericity index were 20 ± 3 mm and 0.36 (0.31-0.39). Although the univariate Cox regression analysis demonstrated that both LV and RV parameters predicted the outcomes, LV parameters no longer predicted them after adjustment. Lower TAPSE (adjusted hazard ratio per 1 mm, 0.84; 95% confidence interval, 0.75-0.93) and higher RV sphericity index (adjusted hazard ratio per 0.1, 1.94; 95% confidence interval, 1.17-3.22) were adverse clinical predictors. In conclusion, the RV structural and functional disorders predict two-year MACCE, whereas the LV parameters do not. Impact of LV impairment can be attenuated after development of RV disorders.

Factors Influencing on the Aneurysm Sac Shrinkage after Endovascular Abdominal Aortic Aneurysm Repair by the Analysis of the Patients with the Aneurysm Sac Shrinkage and Expansion

Objectives: The aneurysmal sac shrinkage has been reported as the strong predictor of favorable long-term outcome after endovascular aneurysm repair (EVAR). We evaluated the effects of perioperative and intraoperative factors on the aneurysm sac shrinkage. Methods: EVAR was performed for 296 patients during August 2009-December 2021. Nine patients with type Ia, Ib, or III; 69 patients with the sac diameter change less than 5 mm; and five patients with sac re-expansion after shrunk more than 5 mm were excluded. Thus, patients with sac shrinkage 5 mm or more (79 patients, shrinkage group) and with sac expansion 5 mm or more (18 patients) were included in this study. Antifibrinolytic therapy with tranexamic acid (TXA) 1500 mg/day for 6 months after EVAR was introduced in March 2013 and patent aortic side branches were coil embolized during EVAR since July 2015. Patients' background and patent aortic side branches at the end of EVAR were evaluated. Results: Univariate analysis for comparison between patients with sac shrinkage and sac expansion revealed that males (82.3% vs. 55.6%, p = 0.021), without antiplatelet therapy (40.5% vs. 66.7%, p = 0.044) and TXA (79.8% vs. 38.9%, p <0.001), were significantly associated with sac shrinkage. By multivariate analysis, the odds ratio of sac shrinkage was 11.7 for males, 0.1 for the patients on antiplatelet therapy, and 6.5 for the patient who received TXA. The patients with patent inferior mesenteric artery (IMA) were less in the shrinkage group (20.3% vs. 77.8%, p <0.001) and with two or less patent lumbar arteries (LAs) were more in the shrinkage group (82.3% vs. 33.3%, p < 0.001). The odd ratio of sac shrinkage was 7.8 for occluded IMA and 3.9 for two or less patent LAs. Conclusion: The possibility of sac shrinkage would be high for the patient with occluded IMA and two or less patent LA at the end of EVAR, and that patient received TXA after EVAR. (This is a translation of Jpn J Vasc Surg 2022; 31: 291-297.).

Operative Timing and Feasibility of Mitral Valve Repair in Active Infective Endocarditis

PURPOSE

We studied the association between operative timing and the feasibility of mitral valve (MV) repair in active infective endocarditis (IE).

METHODS

Forty-nine active IE patients who underwent MV operation were classified according to operative timing: within 48 hours (Term I: n = 7), between 3 and 14 days (Term II: n = 22), and ≥15 days (Term III: n = 20). Patient profiles, operative outcomes, and feasibility of MV repair were evaluated. Complexity score and severity score were used to define the feasibility of MV repair depending on the extent of infected lesion and technical difficulties.

RESULTS

There were no differences in basic profile in the three groups. Rate of major complications was higher in Term I (86%) than II (41%, p = 0.031) and III (25%, p = 0.005). In-hospital mortality was also higher in Term I (43%) than II (9%, p = 0.039) and III (5%, p = 0.015). The three groups did not differ by feasibility of MV repair calculated by the two-score system or by frequency of MV repair (I: 57%, II: 59%, and III: 55%).

CONCLUSIONS

Morbidity and mortality were high in urgent cases. Feasibility of MV repair is associated with the extent of infected lesion and technical difficulties, and not with operative timing.

Procedure and Aortic Remodeling Effects of Entry Closure with Stentgraft for Type B Aortic Dissection: Comparison between the Patients with Narrow True Lumen and Those with Aneurysmal Dilated False Lumen

Objectives: Appropriateness of device selection, procedure protocol and aortic remodeling effects of entry closure (TEVAR) with stent-graft (SG) for patent false lumen type B aortic dissection (TBAD) were compared between the patients with narrow true lumen (narrow group) and those with aneurysmal dilated false lumen (aneurysmal group).

Methods: Twenty-six patients with narrow true lumen (narrow group) and 20 patients with aneurysmal false lumen (aneurysmal group) were included in this study. In narrow group, straight SG was implanted from Zone 3 regardless the distance between the left subclavian artery and entry. In aneurysmal group, straight or taped SG was implanted with proximal landing zone length 20 mm or more. Thoracic aortic anatomy was evaluated by CT and aortic remodeling was defined as true lumen diameter ≥50% of the aortic diameter and occlusion of false lumen. Aorta related death, retrograde type A aortic dissection (RTAD), stentgraft induced new entry (SINE) and aortic maximum diameter enlargement 5 mm or more (aortic expansion) were included in the aortic event.

Results: There was no procedure related complication in narrow group and 1 patient died due to aortic rupture in aneurysmal group, Type Ia endoleak by enhanced CT 7 days after TEVAR was detected in one patient in each group. Achievement of aortic remodeling was significantly better in narrow group. Aortic event occurred in only one patient in narrow group, in whom aortic expansion was observed. In aneurysmal group, aortic event occurred 12 patients (60%) and 2 RTAD, 5 SINE, and 8 aorta expansion were observed. Aortic event free rate was significantly better in narrow group.

Conclusion: TEVAR procedure for the TBAD patients with narrow true lumen seemed to be appropriate, however, different TEVAR procedure or additional procedures would be required for those with aneurysmal dilated false lumen to obtain favorable outcomes. (This is secondary publication from Jpn J Vasc Surg 2021; 30: 347–357.)

Clinical Implications of Determining Individualized Positive End-Expiratory Pressure Using Electrical Impedance Tomography in Post-Cardiac Surgery Patients: A Prospective, Non-Randomized Interventional Study

Optimal positive end-expiratory pressure (PEEP) can induce sustained lung function improvement. This prospective, non-randomized interventional study aimed to investigate the effect of individualized PEEP determined using electrical impedance tomography (EIT) in post-cardiac surgery patients (n = 35). Decremental PEEP trials were performed from 20 to 4 cmH2O in steps of 2 cmH2O, guided by EIT. PEEP levels preventing ventilation loss in dependent lung regions (PEEPONLINE) were set. Ventilation distributions and oxygenation before the PEEP trial, and 5 min and 1 h after the PEEPONLINE setting were examined. Furthermore, we analyzed the saved impedance data offline to determine the PEEP levels that provided the best compromise between overdistended and collapsed lung (PEEPODCL). Ventilation distributions of dependent regions increased at 5 min after the PEEPONLINE setting compared with those before the PEEP trial (mean ± standard deviation, 41.3 ± 8.5% vs. 49.1 ± 9.3%; p < 0.001), and were maintained at 1 h thereafter (48.7 ± 9.4%, p < 0.001). Oxygenation also showed sustained improvement. Rescue oxygen therapy (high-flow nasal cannula, noninvasive ventilation) after extubation was less frequent in patients with PEEPONLINE ≥ PEEPODCL than in those with PEEPONLINE < PEEPODCL (1/19 vs. 6/16; p = 0.018). EIT-guided individualized PEEP stabilized the improvement in ventilation distribution and oxygenation. Individual PEEP varies with EIT measures, and may differentially affect oxygenation after cardiac surgery.

Midterm Outcomes of Endovascular Abdominal Aortic Aneurysm Repair with Prevention of type 2 Endoleak by Intraoperative Aortic Side Branch Coil Embolization

OBJECTIVE

The midterm results of endovascular abdominal aortic aneurysm repair (EVAR) with aortic side branch coil embolization during EVAR was evaluated.

METHODS

Our center began coil embolization for all patent inferior mesenteric artery (IMA) and lumbar artery (LA) with an inner diameter more than 2.0 mm during EVAR since June 2015. When four or more LA were patent, coil embolization for LA with inner diameter 2.0 mm or less was done. EVAR without aortic side branches coil embolization was performed for 59 patients prior to June 2015 (control group) and 79 patients underwent EVAR with coil embolization during EVAR (coil group). The success rate of coil embolization for IMA and LA was evaluated in coil group. The frequency of type 2 endoleak (T2EL), freedom from aneurysm sac expansion (5 mm or more) rate and the rate of the aneurysm sac shrinkage (10 mm or more) were compared between the coil and control groups. Additionally, multiple logistic regression analysis for all patients was conducted to analyze whether IMA patency and the number of patent lumbar artery at the end of EVAR were the risk factors of the aneurysm sac expansion of 5 mm or more.

RESULTS

The success rate of IMA coil embolization was 96.4% and that of LA was 74.5%. Compared to the control group, the frequency of T2EL was significantly lower in coil group at 7 days (1.3% vs. 60.4%, P <0.0001) and at 6 months (2.1% vs 38.2%, P <0.0001) after EVAR. The freedom from aneurysm sac expansion rate was significantly better in the coil group at 5 years (100% in coil group and 65.2% in control group, P = 0.002). The rate of aneurysm sac shrinkage was significantly better in coil group (15.5% vs. 2.0% at 1 year, 42.8% vs. 6.3% at 2 years and 53.4% vs. 17.8% at 3 years, p = 0.0007). The risk of aneurysm sac expansion of 5 mm or more was estimated to be 11 times greater when the IMA was patent, and 4.9 times greater when 3 or more LAs were patent at the end of EVAR.

CONCLUSION

When IMA was occluded and the number of patent LA became 2 or less by aortic side branch coil embolization during EVAR, favorable mid-term results were safely obtained and good long-term result could be expected with EVAR.

Predictive Factor of the Possibility for Aortic Side Branches Coil Embolization during Endovascular Abdominal Aortic Aneurysm Repair

Objective: Coil embolization of aortic side branches has been additionally performed to prevent type II endoleak during EVAR in our institute. In this study, we evaluated the predictive factors of the possibility for coil embolization of the inferior mesenteric artery (IMA) and lumbar artery (LA) during EVAR.

Methods: Seventy-four EVAR patients during June 2015 and April 2019 were included in the study. The coil embolization procedural time for one vessel is limited to 10 min. Aortic side branches were selected with 4 Fr Shepherd hook type catheter (Medikit, Tokyo, Japan) and were embolized with Interlock (Boston Scientific, MA, USA) via microcatheter. As predictive factors, internal diameter of aortic side branches and the aortic diameter perpendicular to the origin of LA (aortic diameter) were evaluated.

Results: Coil embolization was tried for 52 patent IMAs and all IMAs except two IMAs with ostial stenosis were successfully coil embolized (96.2%). Totally 190 LAs were patent and coil embolization was tried for 144 LAs. Among 144 LAs, 106 LAs (73.6%) were successfully coil embolized and the diameter was significantly longer (2.30±0.51 mm vs. 2.04±0.41 mm, p=0.007) and aortic dimeter was significantly shorter (30.0±8.1 mm vs. 40.5±11.6 mm, p<0.001) in successfully embolized LAs. Cut off value of successful LA coil embolization was 2.06 mm for internal diameter and 36.1 mm for aortic diameter by receiver operating characteristic curve analysis. Successful coil embolization rate for LAs with internal diameter longer than 2.0 mm and aortic diameter less than 36.2 mm was 90% (72 among 80 LAs).

Conclusion: Coil embolization during EVAR for IMA was highly successful, if there was no calcified ostial stenosis. LA embolization was feasible especially for LAs with internal diameter ≥2.0 mm and aortic diameter ≤36.1 mm. This information would be useful to select the target vessel for aortic side branches coil embolization during EVAR. (This is a translation of Jpn J Vasc Surg 2019; 28: 389–396.)

Influence of transcatheter aortic valve replacement on patients with severe aortic stenosis undergoing non-cardiac surgery

Objectives

The purpose of this study was to clarify the influence of transcatheter aortic valve replacement (TAVR) in patients with aortic stenosis (AS) undergoing non-cardiac surgery.

Methods

Thirty-four patients with severe AS diagnosed by preoperative evaluation for non-cardiac surgery were reviewed and compared in two categories. First, patient profiles and surgical risk were compared before (pre-TAVR group; n = 10) and after (post-TAVR group; n = 24) the introduction of TAVR. Second, the completion rate of non-cardiac surgery and interval between the two cardiac and non-cardiac operations were compared between surgical aortic valve replacement (AVR) patients before the introduction of TAVR (pre-AVR group (n = 10)), in AVR patients after the introduction of TAVR (post-AVR (n = 12)), and in TAVR patients (TAVR group (n = 12)).

Results

Age and Japan score were higher in the post-TAVR group than in the pre-TAVR group. Malignancy was the most common non-cardiac disease (80%) in the pre-TAVR group, whereas orthopedic disease was the most common (50%) in the post-TAVR group. Completion rate of non-cardiac operation in the pre-AVR, post-AVR and TAVR groups was 70, 33, and 75% (post-AVR vs. TAVR: p = 0.010), and the interval between the two operations was 129 ± 98 days, 87 ± 40 days and 27 ± 15 days, respectively (pre AVR vs. TAVR: p = 0.034 and post AVR vs. TAVR: p = 0.025). In the post-TAVR group, AVR was selected because of a lack of fitness for TAVR in 5 of 12 patients.

Conclusions

After the introduction of TAVR, more senile and high-risk patients became candidates for a two-stage operation, and orthopedic conditions became the most common non-cardiac disease. Innovation in transcatheter valvular interventions and expansion of indications for patients currently evaluated as “unfit for TAVR” might be crucial issues for non-cardiac surgery with severe AS.

[Mitral Valve Plasty in Active Infective Endocarditis]

According to the current guideline, early surgery is recommended in patients with infective endocarditis (IE). On the other hand, mitral valve plasty (MVP) became the preferred surgical option in patients with IE, because of its benefits in the preservation of left ventricular function and prevention of recurrence of infection. Feasibility of MVP is an important issue in surgical strategy, however, it might be associated with the timing of the operation:feasibility of MVP might be higher in healed IE than active IE, although there had been no clear evidence in previous studies. In order to develop scoring system to predict feasibility of MVP in patients with active IE, we have introduced "severity score".Severity score defined as the sum of valvular score which evaluates the extensiveness of the valvular destruction, and technical score which evaluates the complexity and durability of the repair. Probability of feasible MVP was high in severity score≤7 points and low in severity score≥9 points. MVP is basically selected in patients with severity score of 8 points, taking the benefit of patients and risks of longterm durability into consideration. We believe that severity score is valuable and reproducible scoring system in surgical decision making.

Evaluation and Coil Embolization of the Aortic Side Branches for Prevention of Type II Endoleak after Endovascular Repair of Abdominal Aortic Aneurysm

Objectives: Aneurysm shrinkage after EVAR is the strong factor of favorable outcomes after endovascular abdominal aortic aneurysm repair (EVAR), and type II endoleaks is the risk factor of no aneurysm shrinkage or aneurysm enlargement in the long term. In this study, we evaluate the aortic side branches relate to early postoperative type II endoleak, and performed coil embolization for those vessels for prevention of type II endoleak.

Methods: Patency and diameter of aortic side branches including inferior mesenteric artery (IMA) and lumbar artery (LA) were evaluated in 56 consecutive patients with abdominal aortic aneurysm who were scheduled for EVAR. Coil embolization with Interlock was performed in 24 patients during EVAR for all patent IMA and LA with maximal diameter more than 2.0 mm. Computed tomography was performed one week after EVAR for evaluation of endoleak.

Results: In patients with IMA more than 2.5 mm in diameter, the frequency of type II endoleak was approximately 90% regardless of the number of patent LA. In case with patent IMA less than 2.5 mm or with 2 or more patent LA larger than 2.0 mm, the frequency of type II endoleak was 46 to 67%. Coil embolization for IMA was successfully performed in 15/16 patients (94%). Coil embolization of LA was performed for patent LA larger than 2.0 mm and 29 out of 45 LA (64%) were successfully occluded. There was no perioperative complication associated with coil embolization. The frequency of type II endoleak was significantly lower in patients with coil embolization than those without coil embolization (4.2% vs 58.9%, p<0.0001).

Conclusion: Patent IMA and LA in diameter larger than 2.0 mm were associated with type II endoleak one week after EVAR, and coil embolization with Interlock during EVAR is safe and effective procedure to prevent type II endoleak. (This is a translation of Jpn J Vasc Surg 2016; 25: 321–328.)

The Effect of Steroid Therapy on Postoperative Inflammatory Response after Endovascular Abdominal Aortic Aneurysm Repair

Objectives: Unexpected systemic inflammatory response with high fever and increase in C-reactive protein (CRP) occurred frequently after endovascular abdominal aortic aneurysm repair (EVAR). This excessive inflammatory response affects the postoperative course. We evaluated the effects of steroid on the postoperative inflammatory response after EVAR. Methods: Steroid therapy, intravenous infusion of methylprednisolone 1000 mg just after the anesthesia induction, was started since December 2012. After induction of the steroid therapy, 25 patients underwent EVAR with steroid therapy (Group S). These patients were compared with the 65 patients who underwent EVAR without steroid therapy (Group C) in white blood cell count (WBC), CRP and maximum body temperature (BT) on postoperative day 1-5. Results: There was no significant difference in age, female gender, operation time, maximum aneurysm diameter between the two groups. There was no postoperative infective complication in the both groups. WBC did not differ between the two groups; however, CRP was significantly suppressed in Group S than in Group C on POD 1, 3 and 5. Also BT was significantly lower in Group S than Group C on POD 1, 2 and 3. Conclusions: Steroid pretreatment before implantation of the stent graft reduces the early postoperative inflammatory response after EVAR, without increasing postoperative infection. (This is a translation of Jpn J Vasc Surg 2015; 24: 861-865.).

Left atrial thrombus in a patient without mitral valve disease or atrial fibrillation

A 54-year-old man presented with back pain. His medical history included hypertension and gout. There was no history of heart disease or arrhythmia. The electrocardiogram showed normal sinus rhythm. Chest computed tomography demonstrated a large calcified tumor (65 mm) in the left atrium (LA). The echocardiogram showed a round hyperechoic mass in the enlarged LA (56 mm) attached to the atrial septum without mitral valve disease. Urgent surgery for excision of the LA mass with the atrial septum and reconstruction by autologous pericardial patch was performed. There was no pathological change in the mitral valve. Due to surgical injury to the conduction system, implantation of a permanent pacemaker was required postoperatively. Histopathological examination revealed calcification, fibrosis, and thrombus formation. LA thrombus without any history of mitral valve disease or atrial fibrillation is rare. Although the mechanism of the present case was unclear, extensive calcified LA myxoma or undiagnosed patent foramen ovale might have been associated with the disease. <Learning objective: A smooth surface, floating left atrial "ball thrombus" occurs rarely in patients with mitral valve disease or atrial fibrillation. We present a rare case of a giant round left atrial thrombus in a patient without any history of mitral valve disease or atrial fibrillation. Transesophageal echocardiogram showed that the thrombus was round, fixed to the septum, and not floating, and that its surface was calcified. This disease in this patient might have been associated with extensive calcified left atrial myxoma, paroxysmal atrial fibrillation, or undiagnosed patent foramen ovale.>.

Radical Pericardiectomy for Chronic Constrictive Pericarditis

A retrospective analysis was undertaken in 79 patients who underwent pericardiectomy for chronic constrictive pericarditis from January 1985 to February 1999. Most operations (77) were carried out with cardiopulmonary bypass, with subtotal pericardiectomy in 75 patients, and concomitant operations in 25. Postoperative complications occurred in 8 patients: cerebrovascular accident in 2, renal insufficiency in 5, bleeding in 2, low output syndrome in 4, and respiratory insufficiency in 2. The operative mortality was 5%; causes of death were cardiac-related in all cases. Actuarial survival at 1, 5, and 10 years was 89.9% ± 3.4%, 74.9% ± 5.7%, and 55.4% ± 13.5%, respectively. Regression analysis was performed using 53 clinical variables. Female gender, renal insufficiency, concomitant coronary artery bypass grafting, and preoperative right ventricular end-diastolic pressure > 20 mm Hg were found to be predictors of poor survival. At follow-up, improved functional status was noted in 88% of patients. Subtotal pericardiectomy can be performed on cardiopulmonary bypass with low mortality and good long-term survival.

Pulmonary vein obstruction after catheter ablation in a patient with partial anomalous pulmonary vein connection

A 75-year-old man with symptomatic atrial fibrillation was referred to our hospital for catheter ablation. Preprocedural echocardiogram showed mild-moderate degree mitral regurgitation (MR) and mild tricuspid regurgitation (TR) with transvalvular peak gradient (TVPG) of 27 mmHg. The complete isolation of the pulmonary veins was performed by radiofrequency ablation, and the patient was kept in sinus rhythm after the procedure. However, the exertional dyspnea had gradually developed one year after the procedure. Echocardiogram showed severe TR with TVPG 60 mmHg. MDCT showed partial anomalous pulmonary vein connection (PAPVC) of the left upper pulmonary vein and the occlusion of left lower pulmonary vein ostium: pulmonary venous flow of the left upper lung was drained into the brachiocephalic vein. The patient underwent surgical correction of PAPVC and annuloplasty of the mitral and tricuspid valve. Although it is unclear whether there is direct causal relationship between PAPVC and PV obstruction, anatomical evaluation of PVs is important in patients undergoing catheter ablation. <Learning objective: Partial anomalous pulmonary vein connection (PAPVC) is rare and often asymptomatic in adults. In the present case, pulmonary vein obstruction occurred after radiofrequency catheter ablation in a patient with PAPVC. Although pulmonary venous flow from only left upper lobe drained into the brachiocephalic vein before ablation, occlusion of the left lower pulmonary vein resulted in right heart failure one year after ablation.>.

Surgical Outcome in Hemodialysis Patients with Active-Phase Infective Endocarditis

PURPOSE

The aim of this study was to elucidate the characteristics of chronic hemodialysis (HD) patients requiring surgery during the active phase of infective endocarditis (IE).

METHODS

From December 2004 to July 2015, 58 patients underwent surgery in our institute for active IE. Seven patients had been on HD for 1-15 years. Their preoperative profiles and surgical outcomes were compared to those of the other 51 patients (non-HD group).

RESULTS

The predominant causative microorganisms in the HD group were Staphylococcus spp, particularly methicillin-resistant Staphylococcus aureus (MRSA), whereas Streptococcus spp were predominant in the non-HD group. Prosthetic dysfunction (stuck valve after mechanical and structural valve dysfunction following bioprosthetic valve replacement), complete atrioventricular (AV) block, and annular abscess formation were more frequent in the HD group. In-hospital mortality was higher in the HD group (29% vs. 6%, p = 0.044). Actuarial survival in the HD and non-HD groups was 43% vs. 87% at 5 years and 43% vs. 76% at 10 years (p = 0.007).

CONCLUSIONS

Early and long term outcomes in patients with chronic HD were poor. Compared to other patients, chronic HD patients undergoing valve surgery during active IE had higher incidences of MRSA infection, annular abscess formation, postoperative valve dysfunction, and postoperative complete AV block.

Effect of the septal adjustment technique for tricuspid annuloplasty with an MC3 ring

OBJECTIVES

Functional tricuspid regurgitation (FTR) is a significant negative prospective factor for long-term survival in patients with mitral valve disease. Tricuspid annuloplasty (TAP) for FTR is recommended as a concomitant procedure during left-sided valvular surgery. The MC3 annuloplasty ring is designed to restore the dilated tricuspid annulus to its natural three-dimensional shape, but selection of the optimal ring size during TAP is sometimes difficult. One solution is the septal adjustment technique (SAT), in which the point of fixation of the septal portion to the septal annulus is adjusted under confirmation with the water test. Here, we evaluated early outcomes with this new technique.

METHODS

Between January 2008 and September 2014, 56 patients (mean age 67.6 ± 9.0 years, male/female 28/28) with FTR underwent TAP with an MC3 ring. We retrospectively compared early outcomes, including mortality, morbidity and postoperative residual tricuspid regurgitation (TR), between patients undergoing TAP with the SAT (n = 19, Group A) and those undergoing TAP with the conventional technique (n = 37, Group C).

RESULTS

Although preoperative TR grade was significantly higher in Group A than Group C (3.2 ± 0.6 vs. 2.8 ± 0.6, p = 0.032), postoperative TR grade was significantly lower in Group A than Group C (0.9 ± 0.6 vs. 1.4 ± 0.8, p = 0.039), and TR grade was significantly decreased in Group A compared to Group C (2.2 ± 0.9 vs. 1.4 ± 0.8, p = 0.004). TR area reduction was significantly larger in Group A than in Group C (5.21 ± 2.34 vs. 2.85 ± 3.09, p = 0.006).

CONCLUSIONS

The SAT for TAP with an MC3 ring provided better control of postoperative TR than the conventional technique.

[Mitral valve repair in a patient with giant left atrial myxoma;report of a case]

In patients with left atrial myxoma, mitral valve regurgitation is often encountered. However, preoperative assessment of the mitral valve is difficult in cases with giant left atrial myxoma occupying the left atrial cavity. We experienced a patient with giant left atrial myxoma who underwent tumor excision and mitral valve repair. A 40-year-old woman was transferred to the emergency room due to respiratory failure. On admission, her hemodynamic status was unstable and percutaneous cardiopulmonary support was immediately started. Transesophageal echocardiography was performed, which showed giant left atrial tumor with the pedicle on the atrial septum with mitral valve regurgitation, but the severity of regurgitation was unclear. After excision of left atrial myxoma with atrial septum, the mitral valve was examined. The anterior leaflet( A3 scallop) prolapse due to a torn chordae was found. The mitral valve was repaired with leaflet resection and prosthetic ring annuloplasty. Postoperative course was uneventful and postoperative echocardiography showed no residual mitral valve regurgitation. The mitral valve should be carefully inspected intraoperatively after resection of left atrial myxoma, especially when the tumor is gigantic.

[Staged operation of aortic valve stenosis with concomitant sigmoid colon cancer by minimally invasive cardiac surgery; report of a case]

Severe aortic stenosis was found by preoperative echocardiography in a 79-year-old female patient with sigmoid colon cancer. Staged operation was planned. First, bioprosthetic aortic valve replacement was performed by minimally invasive cardiac surgery. She underwent concomitant colostomy to avoid malnutrition which may have occurred in case of colon obstruction. On 25th day after cardiac surgery, curative sigmoidectomy was performed. One year after the operation, she is doing well without any major complications.

Antero-lateral partial sternotomy for extensive thoracic aortic aneurysm

OBJECTIVES

Surgical strategies for patients with aortic arch aneurysm extending to the descending aorta remain controversial. The antero-lateral partial sternotomy (ALPS) approach has been developed as a less invasive alternative single-stage strategy for extensive thoracic arch aneurysm (ETAA).

METHODS

From September 2007 to April 2011, 18 patients underwent elective total arch replacement for ETAA by the ALPS approach (ALPS group). In this approach, a skin incision was made from the bottom of the xiphoid to the anterior axillary line at the third intercostal space with a convex curved line. The thorax was entered through the third intercostal space and a partial lower sternotomy was done. Surgical outcomes were compared with those of 22 patients with ETAA who underwent elective total arch replacement by median sternotomy alone (MS) with regard to the level of distal anastomosis, postoperative complications and mortality.

RESULTS

In the ALPS group, no hospital mortality occurred and one patient experienced pneumonia. No significant difference between the ALPS and MS groups was seen in operative time (384.1 ± 41.6 min vs 402.3 ± 85.3 min P = 0.423) and cardiopulmonary bypass time (220.8 ± 47.1 min vs 236.9 ± 45.4 min P = 0.286). In contrast, distal anastomosis was at a significantly lower vertebral level in the ALPS than in the MS group (5.5 ± 0.4 vs 4.3 ± 0.9, respectively: P < 0.0001).

CONCLUSIONS

The ALPS approach provides good surgical exposure for distal aortic arch aneurysms extending to the descending aorta and ensures the accurate reconstruction of the distal anastomosis without major complications.

Thoracic Endovascular Repair for Aorto-Esophageal Fistula in Patients With Esophageal Carcinoma

Aorto-esophageal fistula (AEF) is a rare complication of esophageal carcinoma. Left untreated, it may be lethal due to massive upper gastrointestinal bleeding, while open thoracic surgery is associated with high operative mortality and morbidity. In contrast, thoracic endovascular aortic repair (TEVAR) for AEF is less invasive than open thoracic surgery. Here, we report 3 successful cases of AEF with esophageal carcinoma treated using TEVAR under local anesthesia in the emergent or urgent phase. General condition of all the patients was dramatically improved, but 1 patient with exsanguinations developed infection of the implanted stent-graft and died due to sepsis. The other 2 patients were treated before esophageal bleeding and remained alive for 1 year without infection. The TEVAR should be considered as early as possible in patients with advanced esophageal carcinoma receiving radiation or chemotherapy who develop early signs of AEF such as symptoms of chest discomfort or descending aortic irregularity on computed tomography scan.

Reconstruction of aorto-mitral continuity with a handmade aorto-mitral bioprosthetic valve for extensive bivalvular endocarditis

Surgical treatment is effective to exclude all infected tissue in patients with infective endocarditis. Although various techniques have been reported, it has remained a great challenge for patients with extensive infected regions. A patient with extensive bivalvular endocarditis including the aortic and mitral valve and aorto-mitral continuity is described. A handmade aorto-mitral bioprosthetic valve was created to reconstruct the defect after extensive debridement. The patient was discharged on the 30th postoperative day without inflammatory signs.

Simple and safe graft insertion in the elephant trunk technique

The elephant trunk technique is a well-established procedure, but aortic wall injury or aneurysmal rupture may occur if the graft is forcibly pushed to insert it into the distal aorta. We have developed simple and safe insertion technique using a syringe.

Mitral valve repair in a patient with acromegaly

We report on a successful mitral valve (MV) repair and modified Cox maze procedure in a 35-year-old male patient with acromegaly, associated with severe mitral regurgitation and atrial fibrillation. He underwent a transsphenoidal adenomectomy, 7 months after the cardiac operation, and IGF-I level was normalized postoperatively. Valvular disease in patients with acromegaly is associated with hormonal activity, and control of growth hormone and insulin-like growth factor I excesses is important in the long-term durability of mitral valve repair.

Significance of mitral valve repair for active-phase infective endocarditis

Mitral valve repair is preferred to replacement in infective endocarditis, but in the active phase, it often requires extensive debridement of infected tissue and complex reconstruction. We investigated 22 consecutive native mitral valve operations during active-phase infective endocarditis. The time from initiation of medical treatment to operation was 16.8 ± 16.4 days. Mitral valve repair was performed in 15 (68.2%) patients, using prosthetic annuloplasty in 14, an autologous pericardial patch in 11, and artificial chordal replacement in 9. Hospital mortality was 9.1% (2 patients), due to subarachnoid hemorrhage and pneumonia. One patient died 26 months after valve replacement due to congestive heart failure. The postoperative left ventricular end-diastolic dimension was significantly smaller (45.7 ± 5.6 vs. 53.3 ± 10.2 mm) and ejection fraction was significantly higher (57.0% ± 14.7% vs. 40.1% ± 8.2%) in patients who underwent valve repair compared to those who had valve replacement. Mitral regurgitation requiring reoperation occurred in 3 patients during follow-up. Mitral valve repair is feasible in active-phase infective endocarditis, and results in improved regression of left ventricular dimensions compared to valve replacement. However, complex mitral valve repair with extensive leaflet resection may not have long-term durability.

Aortic valve replacement in a patient with alpha-thalassemia

Cardiac valve disease resulting from elastic tissue defects has been demonstrated in patients with beta-thalassemia; however, valve disorders of patients with alpha-thalassemia have been rarely discussed. We present the case of a patient with alpha-thalassemia and severe aortic regurgitation with left ventricular dysfunction. The patient underwent successful aortic valve replacement with mechanical prosthesis. Histopathology of the excised valve showed elastic tissue disruption and chronic thrombus on the ventricular side. Hypercoagulative states have been observed in patients with alpha-thalassemia as beta-thalassemia; therefore special attention should be taken in perioperative anticoagulation therapy.

Surgical strategy for subepicardial aneurysm: two case reports

Subepicardial aneurysm is a rare complication of acute myocardial infarction (AMI) and is associated with the risk of spontaneous rupture. We present two patients with subepicardial aneurysms detected after 1 day and 6 weeks after AMI. Both lesions were successfully treated by patch repair.

Hypothermic Circulatory Arrest: Renal Protection by Atrial Natriuretic Peptide

Moderate hypothermic circulatory arrest with selective cerebral perfusion has been developed for cerebral protection during thoracic aortic surgery. However, visceral organs, particularly the kidneys, suffer greater tissue damage under moderate hypothermic circulatory arrest, and acute renal failure after hypothermic circulatory arrest is an independent risk factor for early and late mortality. This study investigated whether atrial natriuretic peptide could prevent the reduction in renal perfusion and protect renal function after moderate hypothermic circulatory arrest. Twelve pigs cooled to 30°C during cardiopulmonary bypass were randomly assigned to a peptide-treated group of 6 and a control group of 6. Moderate hypothermic circulatory arrest was induced for 60 min. Systemic arterial mean pressure and renal artery flow did not differ between groups during the study. However, renal medullary blood flow increased significantly in the peptide-treated group after hypothermic circulatory arrest. Myeloperoxidase activity was significantly reduced in the medulla of the peptide-treated group. Renal medullary ischemia after hypothermic circulatory arrest was ameliorated by atrial natriuretic peptide which increased medullary blood flow and reduced sodium reabsorption in the medulla. Atrial natriuretic peptide also reduced the release of an inflammatory marker after ischemia in renal tissue.

Mycotic aneurysm of the right coronary artery

Mycotic embolism in patients with infective endocarditis is not uncommon, however, mycotic aneurysm of a coronary artery is very rare. We report the case of a 62-year-old woman with mitral valve endocarditis complicated by mycotic aneurysm of the right coronary artery. Mitral valve replacement and resection of the mycotic aneurysm with coronary artery bypass were performed.

[The malignant tumor of the pulmonary artery; report of a case]

Primary sarcoma of the pulmonary artery is rare. Diagnosis is difficult and often delayed; pulmonary embolism is part of the differential diagnosis. We treated a 46-year-old woman with progressive dyspnea. Computed tomography showed a lesion occupying the main pulmonary artery and peripheral branches on both sides. The pulmonary artery tumor, resected under cardiopulmonary bypass, was diagnosed pathologically as intimal sarcoma. Two weeks after the operation, the patient was feeling well and discharged from our hospital. Although the prognosis of pulmonary artery sarcoma is poor, early diagnosis and resection may prolong survival.

Nonocclusive mesenteric ischemia after cardiopulmonary bypass

Nonocclusive mesenteric ischemia (NOMI) is a rare abdominal pathology caused by mucosal hypoperfusion without actual obstruction to the mesenteric arteries. We present a case of NOMI after a cardiopulmonary bypass operation. The patient was a 79-year-old woman with a history of hypertension and diabetes mellitus. A coronary bypass operation was performed with stable hemodynamic conditions, and continuous venovenous hemodialysis was performed on the second postoperative day because of renal insufficiency. After 24 h of hemodialysis, the hematocrit level increased from 29.1% to 36.1%. The patient had some vague abdominal pain on the third postoperative day with abnormal laboratory values: leukocytes 17.10 x 10(3)/microl, creatine kinase 1085 U/l, glutamic-oxyloacetic transaminase 6188 U/l, and lactate dehydrogenase 8695 U/l. Selective angiography showed diffuse stenosis of the superior mesenteric artery (SMA) without any occlusive findings on the major branches; the patient was therefore diagnosed with NOMI. An infusion of urokinase and prostaglandin E1 was started; however, disseminated intravascular coagulopathy had developed and the patient died on the 21st postoperative day as a result of multiple organ failure. The autopsy demonstrated extensive necrosis and hemorrhage in the small intestine without any occlusive findings on the major branches of the SMA.

Aortoplasty with a bovine venous xenograft for pseudoaneurysm after heart transplantation

The case was a 54-year-old man after orthotopic heart transplantation with infected pseudoaneurysm of the ascending aorta. The operation was performed with hypothermic circulatory arrest. Pseudoaneurysm was excised and aortoplasty was performed with a bovine venous xenograft patch. Six months after the operation, and 2 years after transplantation, the patient is doing well.

Risk factor analysis of orthotopic heart transplantation

From March 1989 to December 1999, 1,013 heart transplantations were carried out in this center. Univariate analysis of potential risk factors for early death was followed by stepwise logistic regression to determine independent risk factors. Long-term results were assessed by the Kaplan-Meier method. Multivariate comparisons of long-term results were performed using Cox's proportional hazards model. Early mortality was 8.6%. Actuarial survival was 78.1%, 69.4%, and 53.1% at 1, 5, and 10 years, respectively. Mean total ischemic time was 194 minutes. Independent risk factors of early mortality were female recipient, donor age over 50 years, and ischemic heart disease in the recipient. The precise mechanism of the increased early mortality in female recipients should be studied in the future. Although older donor age was a predictor of early mortality, because of the donor shortage, older hearts should not be excluded from the donor pool. Survival was better in patients with dilative cardiomyopathy than in those with ischemic heart disease.

Creatine kinase and troponin after myocardial preservation using HTK solution (Custoidol) for clinical heart transplantation

Myocardial preservation by Bretschneider histidine-tryptophan-ketoglutarate (HTK) solution (Custoidol) was studied in transplanted patients. Post-operative creatine kinase (CK), CK-MB and troponin I were higher in patients with an ischemic time of >or=4 hours; however, values were within the acceptable range for clinical heart transplantation.

Successful bridging by biventricular pacing for heart transplantation

Biventricular pacing has been proposed recently for treating patients with medically refractory heart failure and ventricular desynchronization. We report the case of a 70-year-old man who had heart transplantation 7 months after implantation of a biventricular pacemaker.

Right ventricular performance during left ventricular unloading conditions: the contribution of the right ventricular free wall

AIM

Right ventricular (RV) dysfunction is a significant complication following implantation of left ventricular assist device (LVAD). However, RV performance after LVAD implantation remains unclear. We have studied the effects of preload and afterload on RV performance under left ventricular (LV) unloading.

METHODS

Six adult mongrel dogs were subjected to cardiopulmonary bypass. RV preload and afterload were independently regulated. Dynamic pressure-length analysis of RV free walls was performed using micromanometer catheter and sonomicrometric dimension transducers. Global RV systolic function was evaluated by the relationship between stroke volume vs. end-diastolic length (EDL) or end-diastolic pressure (EDP). We also examined the afterload dependency of RV performance at constant stroke volume.

RESULTS

Stroke volume vs. EDP and stroke volume vs. EDL demonstrated a linear relationship (r(2) = 0.849 +/- 0.147 and 0.776 +/- 0.121, respectively). At constant stroke volume, RV systolic peak pressure vs. EDL or EDP were shown to have a linear relationship (r(2) = 0.906 +/- 0.050 vs. 0.909 +/- 0.047, respectively).

CONCLUSION

The Frank-Starling relationship for RV performance was shown in this animal model. Without interventricular interaction, RV preload is dependent on RV afterload.

Molecular weight distribution of carrageenans studied by a combined gel permeation/inductively coupled plasma (GPC/ICP) method

Degraded carrageenan (known as poligeenan molecular weight: 20 kDa to 30 kDa) causes ulcerative colitis in experimental animals. In this paper, the molecular weight distributions of 29 samples of food-grade refined carrageenans were studied by high performance liquid gel permeation chromatography (GPC) directly connected to vacuum-ultraviolet inductively coupled plasma-atomic emission spectrometry (ICP) (GPC/ICP) as well as GPC/refractive index (RI) detection. All samples of food-grade carrageenan had a major broad peak of high molecular weight which eluted at around 6.5 min in both RI and ICP mode (sulphur and carbon), and each sample of them had no obvious peak of poligeenan (the detection limit was about 5%). The number average molecular weights of these carrageenans ranged from 193 kDa to 324 kDa, and the weight average molecular weights ranged from 453 kDa to 652 kDa based on RI data. Some samples had a few minor peaks which eluted around 10-12 min. These peaks came from ionic sulphate, sucrose or glucose. It was considered that if the data-sampling programme was improved, the GPC/ICP system would become a more powerful technique for evaluation of carrageenan samples containing ionic substances and sugar.

Pseudoaneurysm after heart transplantation with history of LVAD driveline infection

An infective complication of the aorta is a potential cause of early and late mortality after heart transplantation. We report the case of a 21-year-old male cardiac transplant patient in whom a pseudoaneurysm of the recipient site of ascending aorta coincided with the site of the outflow prosthesis of a preexisting left ventricular assist device; this condition developed 9 months after transplantation.

Prophylactic intravesical instillation of mitomycin C and cytosine arabinoside for prevention of recurrent bladder tumors following surgery for upper urinary tract tumors: a prospective randomized study

BACKGROUND

A recurrence of bladder tumors following surgery for transitional cell carcinoma of the upper urinary tract is not rarely observed. A prospective randomized study was conducted to examine the significance of prophylactic intravesical instillation of mitomycin C (MMC) and cytosine arabinoside (Ara-C) to prevent recurrent bladder tumors after surgery for superficial transitional cell carcinoma of the upper urinary tract.

METHODS

The patients were randomized into an instillation group, who received postoperative intravesical instillation of MMC (20 mg) and Ara-C (200 mg) 28 times over a period of 2 years, and a non-instillation group. The non-recurrence rate was then compared between the groups.

RESULTS

Of the 27 patients registered, 25 patients (13 with instillation and 12 without instillation) were able to be evaluated, with a median follow-up period of 45 months. The non-recurrence rate of bladder tumors in the instillation group was higher than that in the non-instillation group. Although the difference was not statistically significant, the P-value (P = 0.079) demonstrated a strong trend. When any possible bias was allowed for a multivariate analysis, the difference was almost significant (P = 0.0567). No patients withdrew from this study due to any side-effects.

CONCLUSION

The postoperative instillation of MMC and Ara-C may be a useful approach for reducing the recurrence of bladder tumors after surgery for upper urinary tract tumors.

Factors influencing arterial oxygenation early after bidirectional cavopulmonary shunt without additional sources of pulmonary blood flow

OBJECTIVES

Although the arterial oxygen saturation after bidirectional cavopulmonary shunting should theoretically be homogeneous if additional pulmonary flow is obliterated, the arterial oxygen saturation has been found to vary in clinical practice. Knowledge of the preoperative and operative determinants of arterial oxygen saturation early after bidirectional cavopulmonary shunting may lead to a better understanding of this unique physiology.

METHODS

Thirty-five patients who underwent bidirectional cavopulmonary shunting with obliteration of additional pulmonary flow were included in this study. The arterial oxygen saturation was determined at the 5 time points over a 48-hour period. Multivariable regression analysis was used to identify the independent predictors of the arterial oxygen saturation.

RESULTS

No significant interval changes occurred in the arterial oxygen saturation during the 48 hours after bidirectional cavopulmonary shunting, which ranged from 61.6% to 95.6%. There was a significant inverse correlation between the postoperative superior vena cava pressure and the arterial oxygen saturation (P =.003). A low arterial oxygen saturation early after bidirectional cavopulmonary shunting was a predictor of mortality or exclusion from univentricular repair within 24 months (P =.012, odds ratio = 1.14). Of 11 factors identified by univariable analysis, multiple regression analysis indicated that age less than 8 months at the time of shunting (P <.0001) and ventricular volume overload (P =. 002) predicted a lower arterial oxygen saturation after bidirectional cavopulmonary shunting.

CONCLUSIONS

Even without additional sources of pulmonary blood flow, several preoperative factors, including younger age and severe ventricular volume overload, predicted a decrease in the arterial oxygen saturation early after bidirectional cavopulmonary shunting. This, in turn, predicted poor outcome during 2 years of follow-up.

Treating bullous lung disease with Holmium YAG laser in conjunction with fibrin glue and DEXON mesh

BACKGROUND AND OBJECTIVE

Holmium YAG (Ho:YAG) laser energy is highly absorbed by water, and this property is useful to uniformly ablate pulmonary bullae. The current study summarizes the data of a 39-month follow-up of patients treated for bullae with a Ho:YAG laser.

STUDY DESIGN/MATERIALS AND METHODS

We used a Ho:YAG laser from August 1994 to April 1997 to treat small pulmonary bullae in 50 patients. For the first five patients, Ho:YAG laser ablation was followed by resection for histological assessment. In the next six patients, fibrin glue was applied following bullae ablation with the Ho:YAG laser. In all subsequent patients, a DEXON, (polyglycolic acid) mesh patch soaked in fibrin glue was employed after ablation.

RESULTS

From the six patients receiving only the fibrin glue following laser ablation, delayed pneumothorax developed in one patient. In the subsequent 39 patients patched with DEXON mesh soaked in fibrin glue, none encountered delayed pneumothorax.

CONCLUSION

The combined use of fibrin glue and Dexon mesh with the Ho:YAG laser may be an effective technique for treating bullous lung disease.

Modified ultrafiltration improves carbon dioxide removal after cardiopulmonary bypass in infants

Little is known about the role of modified ultrafiltration in ameliorating the adverse effects of the cardiopulmonary bypass on pulmonary function in infants. Twenty-nine nonrandomized consecutive infants (<12 months of age) who underwent unrestrictive ventricular septal defect closure between 1995 and 1998 were included in this study. Down's syndrome was associated in 9 patients. The actual ventilator settings were highly homogeneous among all patients and each time point in the study. Fourteen infants received modified ultrafiltration after the discontinuation of cardiopulmonary bypass. Fifteen untreated patients served as the control group. Correlates of cardiac and pulmonary functions for both groups were compared. The arterial carbon dioxide tension in the experimental group was significantly lower than in the control group from 20 to 240 min after bypass. Arterial oxygenation and pulmonary arterial pressure were similar in the 2 groups. Modified ultrafiltration improves carbon dioxide removal after cardiopulmonary bypass in infants. This may potentially convey a beneficial impact on hemodynamics.