The Use of the Ratio between the Veno-arterial Carbon Dioxide Difference and the Arterial-venous Oxygen Difference to Guide Resuscitation in Cardiac Surgery Patients with Hyperlactatemia and Normal Central Venous Oxygen Saturation

Background：After cardiac surgery,central venous oxygen saturation （ScvO2） and serum lactate concentration are often used to guide resuscitation;however,neither are completely reliable indicators of global tissue hypoxia.This observational study aimed to establish whether the ratio between the veno-arterial carbon dioxide and the arterial-venous oxygen differences （P（v-a）CO2/C（a-v）O2） could predict whether patients would respond to resuscitation by increasing oxygen delivery （DO2）.Methods：We selected 72 patients from a cohort of 290 who had undergone cardiac surgery in our institution between January 2012 and August 2014.The selected patients were managed postoperatively on the Intensive Care Unit,had a normal ScvO2,elevated serum lactate concentration,and responded to resuscitation by increasing DO2 by 〉10%.As a consequence,48 patients responded with an increase in oxygen consumption （VO2） while VO2 was static or fell in 24.Results：At baseline and before resuscitative intervention in postoperative cardiac surgery patients,a P（v-a）CO2/C（a-v）O2 ratio ≥1.6 mmHg/ml predicted a positive VO2 response to an increase in DO2 of〉1 0% with a sensitivity of 68.8% and a specificity of 87.5%.Conclusions：P（v-a）CO2/C（a-v）O2 ratio appears to be a reliable marker of global anaerobic metabolism and predicts response to DO2 challenge.Thus,patients likely to benefit from resuscitation can be identified promptly,the P（v-a）CO2/C（a-v）O2 ratio may,therefore,be a useful resuscitation target.

Surgical treatment of anterior mitral valve prolapse using artificial chordae loop

Artificial chordae replacement with expanded polytetrafluoroethylene （ePTFE; Gore-Tex, W.L.Gore and Associates Inc., Flagstaff, AZ, USA） is an established technique for mitral valve repair with excellent long-term results. There is growing interest in the application of artificial chordae to correct mitral valve regurgitation caused by anterior leaflet prolapse. Application of pre-measured artificial chordae facilitates creation of chordae with appropriate length. The aim of this study was to illustrate the technique for creation of pre-measured artificial chordae.

Clinical features and long-term prognosis of patients with anomalous origin of the left coronary artery from the pulmonary artery

Background Anomalous origin of the left coronary artery from the pulmonary artery （ALCAPA） is a rare congenital heart anomaly. We aimed to illustrate the clinical features and long-term prognosis of patients with ALCAPA.Methods Twenty three patients （13 males and 10 females, ages ranging from 2.5 months to 65 years） identified as ALCAPA in Beijing Anzhen Hospital from April 1984 to June 2009 were divided into two groups, based on the age of onset： group 1 （≤12 months, n=16） and group 2 （〉12 months, n=7）.Results Fifty six point three percent of patients in group 1 had been misdiagnosed as endocardial fibroelastosis （9/16）,18.8% as dilated cardiomyopathy （3/16） and 6.3% as myocardial infarction （1/16）. Patients in group 2 were usually diagnosed as coronary heart disease, myocarditis, or patent ductus arteriosus. Electrocardiography in group 1 revealed abnormal Q waves with T wave inversion in leads I, avL, V4-V6, especially in lead avL （deep and wide Q wave）; but no specific manifestations in group 2. A higher percentage of patients in group 1 had cardiomegaly on chest radiograph （86.7% vs. 33.3%, P=0.031）, while pulmonary artery protrusion was more common in group 2 （26.7% vs. 83.3%,P=0.046）. Lower left ventricular ejection fraction （LVEF） was present in group 1 than in group 2 （（48.5±11.5）% vs.（65.0±6.1）%, P 〈0.001）. Apical ventricular aneurysm （62.5% vs. 0%, P=0.007）, enhanced echogenicity of papillary muscles （87.5% vs. 28.6%, P=0.011） and endocardial thickening （93.8% vs. 14.3%, P 〈0.001） were more frequent in group 1 than in group 2. The ratio of the proximal right coronary artery （RCA） diameter to the aortic root diameter exceeded 0.14 in all cases, more prominent in group 2 （0.26±0.05 vs. 0.33±0.03, P=0.009）. Increased coronary artery collaterals within the interventricular septum were detected in 18 patients （78.3%） by Doppler imaging. Twenty one patients underwent cardiac surgery, including left coronary artery （LCA） ligation （1/21）, LCA ligation plus coronary artery bypass grafting （1/21）, Takeuchi operation （7/21）, and LCA reimplantation surgery （12/21）. Four patients underwent concomitant mitral valve repair and one received mitral valve replacement. Aneurysm resection was performed in 3 cases. Six patients died in hospital after surgery, and the rest of the cohort had no overt symptoms during a follow-up period of 6 to 166 months. Their abnormal Q waves gradually regressed or disappeared, and the LVEF and left ventricle size returned to normal range with alleviation of mitral insufficiency.Conclusions The accurate diagnosis of ALCAPA can be made with serial diagnostic methods. ALCAPA can be successfully treated with several types of cardiac surgery, and surgeries of establishing two-coronary-artery circulation are the preferred operations nowadays, with good long-term prognosis.

Off-pump anteroapical aneurysm plication for left ventricular post-infarction aneurysm： long-term results

Background The temporal response to off-pump anteroapical aneurysm plication has not been well defined. We have evaluated the long-term clinical and functional results of this technique and compared the efficacy with the patch modeling repair. Methods From March 2005 to May 2010, 163 （115 men and 48 women） consecutive patients were operated on for post-infarction left ventricular aneurysm （LVA）, 54 patients underwent patch remodeling （group A） and 109 patients underwent off-pump anteroapical aneurysm plication repair （group B）. All patients had simultaneous coronary revascularization, other operative procedures included septoplasty in eight and ablation of ventricular tachycardia in six. Follow-up ranged from 1 to 5 years, short-term and mid-term outcomes, including complications, cardiac function, and mortality, were assessed. Results Early mortality was 1.8% for all patients （group A 1 death vs. group B 2 deaths, not significant （NS））. Peri-operative support included intraaortic balloon pumping in 16 （9.8%）, （group A 6 patients vs. group B 10 patients, NS） and inotropic drugs in 84 （51.5%）, （group A 34 vs. group B 50, NS）. During a mean follow-up of （3.7±0.8） years, eight patients died, with four due to cardiac-related causes. No patient required transplantation, and two required use of an implantable cardioverter-defibrillator for ventricular tachycardia. Survival at 1 and 5 years was 95% and 86%, respectively. It did not differ significantly between group A and group B. Functional class improved from 2.90±0.59 to 1.65±0.54 among the mid-term survivors （P 〈0.001）, with no significant difference between the two groups. Pre-operative risk factors for mortality or poor function were ejection fraction （EF） 〈0.35 （OR=7.9, 95% CI 1.6-40.0）; congestive heart failure （CHF） （OR=4.4, 95% CI 1.0-19.0）; end-systolic volume index （ESVI） 〉80 ml/m2 （OR=3.7, 95% CI 1.0-14.0）; and advanced age 〉70 years （OR=2.4, 95% CI 1.0-12.0）.

Surgery for sinus of Valsalva aneurysm： 33-year of a single center experience

Background Sinus of Valsalva aneurysm （SVA） is a rare anomaly and few large or long-term series are well established.This study was designed to review 33-year surgical experience of SVA in one center.Methods From August 1980 to December 2013,patients with SVA underwent surgical repair were retrospectively studied.Results A total of 160 patients were identified with mean age of （30±12） years and 112 （70％） of them were males.The right coronary sinus origin of SVA was found in 108 patients （67.5％）,the non-coronary sinus in 51 patients （31.9％）,and the left coronary sinus in one patient （0.6％）.The rupture of 3VA into the right ventricle was identified in 89 （55.6％） cases,the right atrium in 61 （38.1％）,the left ventricle in 2 （1.3％） and no rupture in 8 （5.0％）.Ventricular septal defect （VSD） and aortic regurgitation （AR） were found in 59 （37％） and 45 （28％） patients respectively.An approach via the involved chamber was used in 86 patients （54％）,aortotomy in 8 （5％）,and a combined approach in 66 （41％）.Either direct suture （56,35％） or patch （104,65％） closure were used to repair the SVA.The VSD was closed with a patch （44/59,75％） or direct suture （15/59,25％）.aortic valve replacement （AVR） was performed in 23/45 （51％） and aortic valvuloplasty （AVP） in 9/45 （20％） patients combined with AR.There were 3 hospital deaths （1.9％） and 2 late deaths and 84％ of the patients were followed up for （17.6±4.2） years.New York Heart Association functional class improved significantly after surgery （P＜0.01）.Actuarial survival was 94％ at 10 years,and 88％ at 20 years.Conclusions Surgical treatment of SVA is safe and effective,ruptured SVA or unruptured SVA with VSD and/or AR should be repaired surgically as early as possible.However,late progressive AR is still a risk during long-term follow-up,and early aggressive measures are recommended.These include more use of a combined approach to achieve optimal evaluation of lesions,more patch repairs to reduce the chance of recurrence,and more AVR in patients with moderate to severe AR.

Coarctation of the Aorta with Aortic Arch Hypoplasia：Midterm Outcomes of Aortic Arch Reconstruction with Autologous Pulmonary Artery Patch

Background： Coarctation of the aorta （CoA） with aortic arch hypoplasia （AAH） is a relatively common congenital heart disease in clinical practice. Nonetheless, the corrective surgical technique for infants and children is a clinical problem that remains controversial. In this study, we sought to evaluate the surgical effects of aortic arch （AA） reconstruction with coarctation resection and aortoplasty with autologous pulmonary artery patch for infants and young children with CoA and AAH. Methods： Between January 2009 and December 2015, a total of 22 infants and young children with CoA and AAH who underwent coarctation resection and aortoplasty with autologous pulmonary artery patch were enrolled in this study. The median age of patients was 4.5 （Q1, Q3： 2.0, 14.0） months and the median body weight was 5.75 （Q1, Q3： 4.10, 9.38） kg. All patients were diagnosed with CoA and AAH, and concomitant cardiac anomalies were corrected in one stage. Perioperative and postoperative data were collected and analyzed using the paired sample t-test. Results： No perioperative deaths occurred. No residual obstruction was detected by echocardiography. The postoperative pressure difference across the repaired segment of CoA was 14.05 ± 4.26 mmHg （1 mmHg = 0.133 kPa）, which was smaller than the preoperative pressure difference （48.30 ± 15.73 mmHg; t = -10.119, P 〈 0.001）. The median follow-up time was 29.0 （Q1, Q3： 15.5, 57.3） months. There was no death during the follow-up period, and all patients experienced obvious clinical improvement. Only one child underwent subsequent aortic balloon angioplasty due to restenosis. Computed tomography angiography showed that the AA morphology was smooth, with no aortic aneurysm or angulation deformity. Conclusion： AA reconstruction with coarctation resection and aortoplasty with autologous pulmonary artery patch could effectively correct CoA with AAH, and the rate of reintervention for restenosis is low.

Aortic implantation for anomalous origin of the left coronary artery from the pulmonary artery:A ten-year single center experience

Background At present, creation of a dual coronary system with direct aortic implantation is the preferred management for anomalous origin of left coronary artery from the pulmonary artery （ALCAPA）. However, controversy still exists over the initial management of mitral regurgitation （MR） at the time of ALCAPA repair. Methods Between March 2005 and March 2015, 52 consecutive patients （20 males and 32 females） underwent direct aortic implantation of ALCAPA. Median age at surgery was 10 months （range, 2 to 193）. Mean weight was 9.7_＋7.8 kg. In order to facilitate the analysis, description of MR was given a numeric grade： 0 = none, 1 = trivial, 2 = mild, 2.5 = mild-moderate, 3 = moderate, 3.5 = moderate-severe, and 4 = severe. Results The LV shortening fraction （LVFS） demonstrated significant improvement between presentation and discharge （32.1±10.1% vs. 28.6±9.6%, P = 0.023）, and there was also significant improvement in the mean MR grade between presentation and discharge （2.40＋1.16 vs. 2.91＋ 1.19, P = 0.001）. There were 4 hospital deaths （7.7%）. The median follow-up was 21 months （range 1.5 to 111）, 3 patients （5.8%） were lost to follow-up, 1 patient required reoperation for mitral valve replacement. Significant improvement was seen in LVFS between discharge and late follow-up （38.0±6.0% vs. 32.1±10.1%, P = 0.001）, however, the degree of MR did not dem- onstrate further change （2.29_＋1.20 vs. 2.40＋1.16, P = 0.541）. Conclusion Creation of a dual coronary system with direct aortic implantation of the left coronary artery results in complete recovery of left ventricular function. Concomitant mitral valve （MV） repair for ALCAPA patients with moderate-severe and severe MR is helpful to early MV function recovery.

Anteroapical aneurysm plication improves mechanical intraventricular dyssynchrony in patients with anterior myocardial infarction

Background Left ventricular （LV） dyssynchrony has been described to occur in patients with myocardial infarction. Dyssynchrony of left ventricular mechanical contraction produces adverse hemodynamic consequences. This study aimed to test the capacity of geometric rebuilding by aneurysm plication to restore a more synchronous contractile pattern after a mechanical, rather than electrical, intervention. Methods A total of sixty patients with anterior myocardial infarction, QRS duration 〈120 ms, electively undergoing operation between January 2008 and January 2010 were included for analysis. Real-time 3-dimensional echocardiography was performed to assess LV function, LV systolic and diastolic dyssynchrony by measuring ejection fraction （EF）, peak ejection rate （PER）, peak filling rate （PFR） and LV dyssynchrony. LV dyssynchrony was defined as the systolic dyssynchrony of the time to reach the minimum systolic volume for 16 LV segments, expressed in percent cardiac cycle, systolic dyssynchrony index （SDI）. We compared changes of LV dyssynchrony at different interval times. Results LV contraction was significantly asynchronous because preoperative SDI was higher, EF, PER and PFR were lowered. Compared with function after operation, LV mechanical intraventricular resynchronization was improved with decreased SDI （（8.7_＋0.5） % vs. （14.3_＋1.6） %, P=0.01）; LV function was improved with EF increasing （（43_＋9）% vs. （37_＋7）%, P=0.001）, and LV systolic and diastolic dyssynchrony was improved with more rapid PFR （199.4_＋15.6 vs. 148.4_＋21.2, P=0.002） and PER （212.4_＋14.5 vs. 156.3_＋_26.2, P=0.001）. Conclusions Systolic and diastolic dyssynchrony was highly prevalent in patients with aneurysm, irrespective of QRS duration. Aneurvsm olication oroduces a mechanical intrave.ntricular rP.~vnc.hrnniTation.