Use of cardiopulmonary bypass is associated with chronic postsurgical pain among patients undergoing coronary artery bypass graft surgery: follow-up of a randomized, clinical trial.

BACKGROUND: Chronic postsurgical pain (CPSP) worsens patients' mortality, morbidity, and quality of life. Cardiopulmonary bypass is mandatory for cardiac surgery, but it induces intense inflammation. The presence of inflammation is a crucial part of pain sensitization. An extreme inflammatory response due to cardiopulmonary bypass might cause a high prevalence of CPSP after cardiac surgery. We hypothesized that the prevalence and severity of CPSP are higher in patients after on-pump coronary artery bypass graft (CABG) surgery than in those after off-pump CABG surgery. METHODS: This prospective, observational study was performed on a cohort from a randomized trial (on-pump CABG: 81 patients, off-pump CABG: 86 patients). A questionnaire about the severity of surgical wound pain that evaluated pain with the numerical rating scale (NRS) was filled out by the patients. NRS responses for current pain, peak pain in the last 4 weeks, and average pain in the last 4 weeks were evaluated. The main outcomes were the severity of CPSP as evaluated using the NRS and the prevalence of CPSP. CPSP was defined as pain with an NRS score > 0. Differences in severity between groups were analyzed using multivariate ordinal logistic regression models adjusted for age and sex, and differences in prevalence between groups were analyzed using multivariate logistic regression models adjusted for age and sex. RESULTS: The questionnaire return rate was 77.0%. During a median follow-up of 17 years, 26 patients complained of CPSP (on-pump CABG: 20 patients, off-pump CABG: 6 patients). Ordinal logistic regression showed that the NRS response for current pain (odds ratio [OR] 2.34; 95% CI 1.12-4.92; P = 0.024) and the NRS response for peak pain in the last 4 weeks (OR 2.71; 95% CI 1.35-5.42; P = 0.005) were significantly higher in patients who underwent on-pump CABG surgery than in those who underwent off-pump CABG. Logistic regression showed that on-pump CABG surgery was an independent predictor of CPSP (OR 2.59; 95% CI 1.06-6.31; P = 0.036). CONCLUSIONS: The prevalence and severity of CPSP are higher in patients with on-pump CABG surgery than in those with off-pump CABG surgery.

Effect of cerebrospinal fluid drainage pressure in descending and thoracoabdominal aortic repair: a prospective multicenter observational study.

PURPOSE: Cerebrospinal fluid drainage (CSFD) is recommended during open or endovascular thoracic aortic repair. However, the incidence of CSFD complications is still high. Recently, CSF pressure has been kept high to avoid complications, but the efficacy of CSFD at higher pressures has not been confirmed. We hypothesize that CSFD at higher pressures is effective for preventing motor deficits. METHODS: This prospective observational study included 14 hospitals that are members of the Japanese Society of Cardiovascular Anesthesiologists. Patients who underwent thoracic and thoracoabdominal aortic repair were divided into four groups: Group 1, CSF pressure around 10 mmHg; Group 2, CSF pressure around 15 mmHg; Group 3, CSFD initiated when motor evoked potential amplitudes decreased; and Group 4, no CSFD. We assessed the association between the CSFD group and motor deficits using mixed-effects logistic regression with a random intercept for the institution. RESULTS: Of 1072 patients in the study, 84 patients (open surgery, 51; thoracic endovascular aortic repair, 33) had motor deficits at discharge. Groups 1 and 2 were not associated with motor deficits (Group 1, odds ratio (OR): 1.53, 95% confidence interval (95% CI): 0.71-3.29, p = 0.276; Group 2, OR: 1.73, 95% CI: 0.62-4.82) when compared with Group 4. Group 3 was significantly more prone to motor deficits than Group 4 (OR: 2.56, 95% CI: 1.27-5.17, p = 0.009). CONCLUSION: CSFD is not associated with motor deficits in thoracic and thoracoabdominal aortic repair with CSF pressure around 10 or 15 mmHg.

Anesthesia during delivery in pregnant women with dilated cardiomyopathy.

Emergency cesarean delivery in patients with heart failure increases maternal and fetal mortality. The present study aimed to identify the relationship between the use of anesthesia for delivery and progressive cardiac deterioration in women with dilated cardiomyopathy (DCM) and to examine its implications on maternal and fetal outcomes. Twenty-nine pregnancies in 25 women with DCM from the National Cerebral and Cardiovascular Center Hospital (Suita, Japan) were included in this retrospective longitudinal study. Fourteen of the patients (48.3%) delivered via cesarean section. Among these, 4 patients (13.8%) experienced heart failure within 42 days of delivery. The indication for cesarean delivery was heart failure in 3 patients and induction failure in 1 patient. The types of anesthesia used for these patients included general (n = 1), combined spinal-epidural (n = 2), and epidural (n = 1). Two of these cesarean deliveries were performed preterm. The left ventricular ejection fraction of patients with heart failure was ≤ 35% before 34 weeks gestation. Among the 25 patients without heart failure, 2 exhibited a left ventricular ejection fraction of ≤ 35% before 34 weeks gestation. Meanwhile, the types of anesthesia used for remaining 10 patients who did not experience heart failure included general (n = 1), combined spinal-epidural (n = 8), and epidural (n = 1). The rate of general anesthesia was 25% in patients who experienced heart failure and 4% in others. There was no incidence of maternal or fetal death. A preterm anesthetic evaluation may be warranted to optimize anesthetic management when the ejection fraction decreases to ≤ 35% before 34 weeks gestation in patients with DCM.

Prevalence and Severity of Aortic Regurgitation Due to a Percutaneous Left Ventricular Assist Device (Impella 5.0): A Retrospective Observational Study.

OBJECTIVES: Placement of the Impella 5.0 percutaneous left ventricular assist device may cause aortic regurgitation (AR) due to malcoaptation of the aortic leaflets. The authors investigated the prevalence and severity of AR during Impella 5.0 support. DESIGN: Retrospective observational study. SETTING: An academic hospital. PARTICIPANTS: A total of forty-two consecutive patients who underwent Impella 5.0 implantation from April 2018 to March 2022. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: To investigate AR prevalence, the authors calculated the AR volume by subtracting left ventricular inflow from left-sided systemic flow, the latter of which consisted of flow through the Impella 5.0 cannula and across the aortic valve. Because it is challenging to estimate flow across the aortic valve as distinct from that through Impella 5.0, the authors analyzed 19 of 42 patients whose aortic valves were closed (ie, those with no spontaneous cardiac output). AR due to Impella 5.0 was considered present if the AR fraction was ≥7%. The median AR volume was 0.6 L/min (interquartile range: 0.4-1.5 L/min), which was 13.5% (interquartile range: 11.0 to 30.6%) of the median Impella 5.0 flow. Seventeen of the 19 patients (89.5%) were diagnosed with AR during Impella 5.0 support, and the severity of AR was mild in 11 patients (57.9%) and moderate in 6 (31.6%). CONCLUSIONS: The authors revealed a high prevalence of AR during Impella 5.0 support in patients with no spontaneous cardiac output. Moreover, 31.6% of patients had moderate AR.

Quantitative regional cerebral blood flow measurement using near-infrared spectroscopy and indocyanine green in patients undergoing superficial temporal to middle cerebral artery bypass for moyamoya disease: a novel method using a frequency filter.

Measuring regional cerebral blood flow (rCBF) after revascularization for moyamoya disease, as a type of ischemic cerebrovascular disease, is crucial. This study aims to validate our novel technology that combines near-infrared spectroscopy (NIRS) with a frequency filter to extract the arterial component. We measured rCBF before and after revascularization for moyamoya disease and at the end of the surgery using NIRO-200NX (Hamamatsu Photonics, Japan) and indocyanine green (ICG). rCBF was calculated using Fick's principle, change in arterial ICG concentrations, and maximum arterial ICG concentration. rCBF measured with NIRS (rCBF_N) was compared with pre- and postoperative rCBF measured with SPECT (rCBF_S). Thirty-four procedures were analyzed. rCBF_N increased from baseline to end of the surgery (mean difference (MD), 2.99 ml/min/100 g; 95% confidence interval (CI), 0.40-5.57 ml/min/100 g on the diseased side; MD, 4.94 ml/min/100 g; 95% CI, 2.35-7.52 ml/min/100 g on the non-diseased side). Similar trends were observed for rCBF_S (MD, 3.98 ml/min/100 g; 95% CI, 2.30-5.67 ml/min/100 g on the diseased side; MD, 2.77 ml/min/100 g; 95% CI, 1.09-4.45 ml/min/100 g on the non-diseased side). Intraclass correlations 3 (ICC3s) between rCBF_N and rCBF_S were weak on the diseased side (ICC3, 0.25; 95% CI, -0.03-0.5; p = 0.07) and the non-diseased side (ICC3, 0.24; 95% CI, -0.05-0.5; p = 0.08). rCBF measurements based on this novel method were weakly correlated with rCBF measurements with SPECT.

Early Atrial Tachyarrhythmia Recurrence Predicts Late Atrial Tachyarrhythmia Recurrence After the Cryo-Maze Procedure　- An Observational Study.

BACKGROUND: It is unknown whether early atrial tachyarrhythmia (ATA) recurrence occurring within 3 months after the Maze procedure predicts late ATA recurrence.Methods and Results: This study involved 610 patients who underwent the modified Cryo-Maze procedure in conjunction with other cardiac surgery. The primary outcomes were late ATA recurrence, defined as occurring ≥3 months after surgery. The effects of early ATA recurrence on late ATA recurrence were analyzed using a Cox proportional hazards model. The following 11 covariates were considered explanatory variables: early ATA recurrence, age, sex, body surface area, preoperative duration of atrial fibrillation, preoperative left atrial diameter, and concomitant surgery (mitral valve replacement, mitral valve repair, aortic valve replacement, tricuspid annuloplasty, and left atrial appendage closure). Statistical analyses were performed with a 2-sided 5% significance level. Early ATA recurrence occurred in 174 patients (28.5%). Late ATA recurrence occurred in 167 patients (27.5%), with 595 events identified in these patients. The Cox proportional hazards model showed that early ATA recurrence was an independent predictor of late ATA recurrence (hazard ratio, 4.14; 95% confidence interval, 3.00-5.70; P<0.001)Conclusions: Early ATA recurrence was an independent predictor of late ATA recurrence among patients undergoing the modified Cryo-Maze procedure. The blanking period might not be applied to patients undergoing the modified Cryo-Maze procedure.

Two cases of catheters inserted from the femoral vein straying into the hepatic vein, possibly owing to a Eustachian valve: a case report.

BACKGROUND: In minimally invasive cardiac surgery (MICS) and extracorporeal membrane oxygenation (ECMO), a guidewire is inserted from the femoral vein (FV) into the right atrium. However, rarely, the guidewire or catheter strays into the hepatic vein (HV) because of the inferior vena cava (IVC)-HV angle. We report two cases in which a guidewire and venous cannula from the FV strayed into the HV, likely owing to a Eustachian valve. CASE PRESENTATION: Both patients were women who underwent transesophageal echocardiography-guided FV cannulation. In case 1, a guidewire from the FV strayed into the HV owing to a Eustachian valve. In case 2, ECMO was established postoperatively. Transthoracic echocardiography confirmed the venous cannula had strayed into the HV. Computed tomography indicated IVC-HC angles of 129° (case 1) and 102° (case 2). CONCLUSION: A Eustachian valve can impede devices inserted from the FV and even allow them to stray into the HV.

U-shaped association between elapsed time after surgery and the intensity of chronic postsurgical pain following cardiac surgery via thoracotomy: an observational cohort study.

BACKGROUND: Chronic postsurgical pain (CPSP) is defined as chronic pain that develops or increases in intensity after a surgical procedure and persists beyond the healing process, defined as at least 3 months postoperatively. However, the rationale behind this time period is weak. METHODS: This prospective observational study included a total of 238 consecutive patients who underwent mitral valve repair via thoracotomy. A questionnaire consisting of a numerical rating scale (NRS) to assess the severity of postsurgical pain was mailed to each participant more than 3 months after the operation. The outcomes of interest were current pain, peak pain in the last 4 weeks, and average pain in the last 4 weeks, each assessed using the NRS. The nonlinear associations between the elapsed time after surgery and the intensity of CPSP were evaluated. All statistical analyses were performed with a two-sided significance level of 5%. RESULTS: Two-hundred and ten patients (88.2%) answered the questionnaire. There was a significant nonlinear association between the elapsed time after surgery and each NRS response (all, P < 0.05). The lowest adjusted log odds of current pain, peak pain in the past 4 weeks, and average pain in the past 4 weeks were - 1.49, - 1.13, and - 1.26 at 33, 33, and 33 months postoperatively, respectively. CONCLUSIONS: There was a significant U-shaped association between the elapsed time after surgery and intensity of CPSP. The adjusted log odds of each NRS response was lowest at 33 months after cardiac surgery via thoracotomy.

Abnormally high Patient State Index associated with epicardial pacing: a case report.

BACKGROUND: Anesthesiologists monitor electroencephalography (EEG) intraoperatively to maintain adequate depth of anesthesia. However, the EEG signal is affected by noise and interference. The SedLine® is a brain function monitor with which the Patient State Index (PSI) is calculated. In this study, we report abnormally high PSI values associated with epicardial pacing during open heart surgery. CASE PRESENTATION: A 50-year-old man was scheduled for total arch replacement. Atrial demand pacing was started before weaning from cardiopulmonary bypass. The PSI increased from 30 to 80 soon after the start of pacing, and the EEG waveform showed spikes synchronized with the pacing. As the pacing output was lowered, the spikes on the EEG attenuated and disappeared, and the PSI decreased to < 40. When the pacing output was increased again, the spikes recurred, and the PSI increased again. CONCLUSIONS: Pacemaker spikes may cause contamination of the EEG, resulting in abnormally high PSI values.

Cardiac surgery improves the postoperative frailty score of frail patients.

BACKGROUND: Cardiac surgery in frail patients has been reported to be associated with increased mortality and morbidity but may improve functional status of frail patients. Few studies have investigated the impact of cardiac surgery on the trajectory of postoperative frailty. We hypothesized that cardiac surgery in frail patients would improve frailty postoperatively. METHOD: This study included 71 patients over 65 years old who were scheduled for cardiac surgery via sternotomy or thoracotomy. Frailty was prospectively evaluated using the Kihon Checklist (KCL) at 1 and 3 months postoperatively. Patients were divided into three groups based on the preoperative KCL score: nonfrail, prefrail, and frail. The interaction between the degree of preoperative frailty and the trajectory of postoperative KCL scores was assessed. RESULTS: The KCL score changed significantly over time (P < 0.001), and the KCL score trajectory differed significantly according to the degree of preoperative frailty (P for interaction = 0.003). In the frail group, the KCL score was significantly lower 3 months postoperatively than preoperatively (median 8, interquartile range [5, 9] versus median 9, interquartile range (9, 13), P = 0.029). CONCLUSION: The trajectory of postoperative KCL scores differed significantly depending on the degree of preoperative frailty. At 3 months after cardiac surgery, the KCL score of frail patients was significantly improved, while that in nonfrail patients was significantly deteriorated.

Aortic valve insufficiency after Impella device insertion that required aortic valve replacement after Heart Mate III left ventricular assist device implantation: a case report.

The Impella (Abiomed, Danvers, MA, USA) is a minimally invasive axial-flow catheter used in severe heart failure. We describe a case in which aortic insufficiency occurred after Impella insertion, required extra surgical intervention twice. A 33-year-old man with familial dilated cardiomyopathy was admitted to our hospital due to acute decompensation of heart failure. Despite intensive medical treatment, his hemodynamic status did not improve. Firstly, Impella was emergently implanted, and HeartMate III (Abbott, Plymouth, MN, USA) implantation was performed 2 weeks after. In the HeartMate III implantation, new aortic insufficiency had revealed and central aortic valve closure was performed concomitantly. However, on postoperative Day1, the coaptation stitch had untied, causing severe aortic insufficiency which led to another emergent operation of aortic valve replacement. We suggest that indications for Impella implantation need to be carefully discussed beforehand, especially with patients who may undergo implantation of left ventricular assist device.

Correlation Between Intraventricular Pressure Difference and Indexed Flow of a Left Ventricular Assist Device.

OBJECTIVES: There is no definitive parameter for left ventricular (LV) preload in patients with a continuous-flow left ventricular assist device (LVAD). The intraventricular pressure difference (IVPD) is the maximum pressure difference between the mitral valve and LV apex during diastole; and, in past studies, the IVPD was influenced by volume loading. The authors hypothesized that IVPD in LVAD patients correlates with indexed LVAD flow and that IVPD can serve as a novel parameter of LV preload in this population. DESIGN: A single-center, retrospective, observational study. SETTING: A tertiary-care hospital from August 2019 to July 2020. PARTICIPANTS: Sixteen ramp tests for adjustment of LVAD pump speed in 14 adult patients undergoing continuous-flow LVAD implantation. INTERVENTIONS: Measurement of IVPD during ramp tests. MEASUREMENTS AND MAIN RESULTS: LVAD flow and IVPD were measured at each LVAD pump speed during the ramp test for the adjustment of LVAD pump speed after patients came off cardiopulmonary bypass during LVAD implantation. A straight, longitudinal view of the left atrium and left ventricle was obtained, and the pressure difference between the mitral valve and LV apex during diastole was measured by transesophageal echocardiography. The maximum pressure difference during diastole was recorded as IVPD. The relationship between indexed LVAD flow (LVAD flow/body surface area) and IVPD was assessed by a multivariate nonlinear regression analysis with the Huber-White sandwich estimator. IVPD correlated with indexed LVAD flow (p < 0.001). CONCLUSIONS: IVPD is a useful indicator of LV preload during LVAD implantation.

Association Between Sternotomy Versus Thoracotomy and the Prevalence and Severity of Chronic Postsurgical Pain After Mitral Valve Repair: An Observational Cohort Study.

OBJECTIVE: Investigate differences in the prevalence and severity of chronic postsurgical pain (CPSP) after cardiac surgery via thoracotomy versus sternotomy are not well-understood. DESIGN: An observational cohort study. SETTING: A tertiary care hospital. PARTICIPANTS: Four hundred twenty-eight patients (sternotomy: 192 patients, thoracotomy: 236 patients) who underwent mitral valve repair. INTERVENTIONS: A questionnaire about the severity of surgical wound pain evaluated with a numerical rating scale (NRS) was sent. NRS responses for current pain, peak pain in the last four weeks, and average pain in the last four weeks were evaluated. MEASUREMENTS AND MAIN RESULTS: The main outcomes were the severity of CPSP evaluated using NRS and the prevalence of CPSP. CPSP was defined as pain >0 that developed after a surgical procedure. During the median follow-up of 29 months, 79 patients complained of CPSP. (sternotomy: 15 patients, thoracotomy: 64 patients). Multivariate ordinal logistic regression showed that NRS responses for current pain (adjusted odds ratio [aOR], 3.17; 95% confidence interval [CI] 1.64-6.12; p = 0.001), peak pain in the last four weeks (aOR, 2.00; 95% CI 1.11-3.61; p = 0.021), and average pain in the last four weeks (aOR, 2.21; 95% CI 1.31-3.72; p = 0.003) were significantly higher in patients who underwent thoracotomy. Multivariate logistic regression showed that thoracotomy was an independent predictor of CPSP (aOR, 3.63; 95% CI 1.67-7.88; p = 0.001). CONCLUSIONS: The prevalence and severity of CPSP were higher among patients who underwent mitral valve repair via thoracotomy than sternotomy.

Impact of Balloon Postdilation on Six-Year Mortality After Transcatheter Aortic Valve Replacement.

OBJECTIVES: Balloon postdilation (BPD) is one strategy for decreasing paravalvular leakage, but its effect on long-term mortality remains unclear. The authors sought to clarify whether BPD influences long-term mortality of patients with transcatheter aortic valve replacement (TAVR). DESIGN: Single-center retrospective study. SETTING: National heart center; single institution. PARTICIPANTS: Participants were patients who underwent TAVR in the authors' hospital from January 2014 to December 2016. A balloon-expandable Sapien XT or Sapien3, or self-expandable CoreValve or Evolute R, was implanted according to the decision of the surgeon considering degree of calcification of the aortic valve. INTERVENTIONS: No interventions. MEASUREMENTS AND MAIN RESULTS: Multivariate Cox regression analysis and inverse probability weighted estimation were performed using a propensity score to examine whether BPD influenced six-year mortality. Ultimately, 180 patients were analyzed. During the follow-up period, with a median of 1104 (interquartile range: 730-1463) days, 41 patients died and cumulative incidence of mortality at six years was 22.8%. Society of Thoracic Surgeons score (odds ratio [OR]: 2.257, 95% CI: 1.213-4.197, p = 0.010)], BPD (OR: 0.306, 95% CI: 0.098-0.953, p = 0.041), and paravalvular regurgitation of at least moderate-to-mild severity after deploying (OR: 5.407, 95% CI: 1.626-17.978, p = 0.006) were significant factors of mortality. CONCLUSIONS: BPD is associated with reduced six-year mortality.

Accuracy and Trending Ability of Cardiac Index Measured by the CNAP System in Patients Undergoing Abdominal Aortic Aneurysm Surgery.

OBJECTIVES: The CNAP system is a noninvasive monitor that provides a continuous arterial pressure waveform using an inflatable finger cuff. The authors hypothesized that dramatic changes in systemic vascular resistance index during abdominal aortic aneurysm (AAA) surgery might affect the accuracy of noninvasive pulse contour monitors. The aim of this study was to evaluate the accuracy and trending ability of cardiac index derived by the CNAP system (CICN) in patients undergoing AAA surgery. DESIGN: Prospective clinical study. SETTING: Cardiac surgery operating room in a single cardiovascular center. PARTICIPANTS: Twenty patients who underwent elective AAA surgery. INTERVENTIONS: CICN and cardiac index measured using 3-dimensional images (CI3D) were determined simultaneously at 8 points during the surgery. At aortic clamping and unclamping, the authors tested the trending ability of CICN using 4-quadrant plot analysis and polar plot analysis. MEASUREMENTS AND MAIN RESULTS: The authors found a wide limit of agreement between CICN and CI3D (percentage error: 85.0%). The cubic splines, which show the relationship between systemic vascular resistance index and percentage CI discrepancy [(CICN-CI3D)/CI3D], were sloped positively. Four-quadrant plot analysis showed poor trending ability for CICN at both aortic clamping and unclamping (concordance rate: 29.4% and 57.9%, respectively). In the polar plot analysis, the concordance rates at aortic clamping and unclamping were 15.0% and 35.0%, respectively. CONCLUSIONS: CICN is not interchangeable with CI3D in patients undergoing AAA surgery. The trending ability for CICN at aortic clamping and unclamping was below the acceptable limit. These inaccuracies might be secondary to the high systemic vascular resistance index during AAA surgery.

Anesthesia for Cesarean Section and Postpartum Cardiovascular Events in Congenital Heart Disease: A Retrospective Cohort Study.

OBJECTIVE: To clarify the association between anesthetic technique and maternal and neonatal outcomes in parturients with congenital heart disease (CHD). DESIGN: Retrospective, observational cohort study. SETTING: An academic hospital. PARTICIPANTS: A total of 263 consecutive parturients with CHD who underwent cesarean section from 1994 to 2019. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: The authors compared postpartum cardiovascular events (composite of heart failure, pulmonary hypertension, arrhythmia, and thromboembolic complications) and neonatal outcomes (intubation and Apgar score <7 at one or five minutes) by anesthetic technique. Among 263 cesarean sections, general anesthesia was performed in 47 (17.9%) parturients and neuraxial anesthesia in 214 (81.3%) parturients. Cardiovascular events were more common in the general anesthesia group (n = 7; 14.9%) than in the neuraxial anesthesia group (n = 17; 7.9%). Generalized linear mixed models assuming a binomial distribution (ie, mixed-effects logistic regression), with a random intercept for each modified World Health Organization classification for maternal cardiovascular risk, revealed that general anesthesia was not significantly associated with cardiovascular events (odds ratio [OR], 1.00; 95% confidence interval [CI], 0.30-3.29). In addition, general anesthesia was associated with composite neonatal outcomes (Apgar score <7 at one or five minutes or need for neonatal intubation; OR, 13.3; 95% CI, 5.52-32.0). CONCLUSION: Anesthetic technique is not significantly associated with postpartum composite cardiovascular events. General anesthesia is significantly associated with increased need for neonatal intubation and lower Apgar scores.

U-Shaped Association Between Intraoperative Net Fluid Balance and Risk of Postoperative Recurrent Atrial Tachyarrhythmia Among Patients Undergoing the Cryo-Maze Procedure: An Observational Study.

OBJECTIVE: The ability of perioperative fluid management to prevent postoperative recurrence of atrial tachyarrhythmia remains controversial. The aim of the present study was to assess if intraoperative net fluid balance was associated with atrial tachyarrhythmia recurrence after the Cryo-Maze procedure. DESIGN: An observational cohort study. SETTING: A tertiary care hospital from April 2007 to May 2019. PARTICIPANTS: Four hundred forty-four patients undergoing the Cryo-Maze procedure in conjunction with other cardiac surgeries. INTERVENTIONS: The Cryo-Maze procedure in conjunction with other cardiac surgeries. MEASUREMENTS AND MAIN RESULTS: The main outcome was early atrial tachyarrhythmia recurrence, consisting of atrial fibrillation, atrial flutter, or atrial tachycardia, within the first three months after surgery. Complete follow-up was achieved in 443 patients (99.8%), of them 127 (28.6%) developed early atrial tachyarrhythmia recurrence. The median intraoperative net fluid balance was 1,627 mL (interquartile range, -215 to 3,557 mL). Multivariate logistic regression showed that intraoperative net fluid balance (p = 0.001), preoperative AF duration (adjusted odds ratio, 1.40; 95% CI, 1.17-1.68; p < 0.001) and left atrial volume index (aOR, 1.61; 95% CI, 1.06-2.45; p = 0.025) were independent predictors of early atrial tachyarrhythmia recurrence. The adjusted log odds were lowest (-1.52) when net fluid balance was 1,557 mL. CONCLUSIONS: There is a significant U-shaped association between intraoperative net fluid balance and early atrial tachyarrhythmia recurrence among patients undergoing the Cryo-Maze procedure.