An analysis of the learning curve for robotic-assisted mitral valve repair.

BACKGROUND: Many cardiac surgeons receive training for sternotomy-based cardiac surgical operations in residency programs and only a few education programs offer training specifically in minimally invasive cardiac surgery. In this report, we aimed to search and analyze the learning curve for robotic-assisted mitral valve (MV) repair in cardiac surgeons. METHOD: Between January 2010 and July 2019, 60 robotic-assisted isolated MV repair surgeries were performed with DaVinci Robotic Systems in our center. Different kinds of surgical techniques were used. The assessment of the learning curve was based on cardiopulmonary bypass (CPB) and transthoracic aortic clamp (CC) times. RESULT: There were 23 (38.3%) men and 37 (61.7%) women with a mean age of 48.3 years. The lesions of the MV were posterior leaflet prolapsus (n = 42, 70.0%), anterior leaflet prolapsus (n = 8, 13.3%), Barlow disease (n = 3, 5%), and annular dilatation (n = 7, 11.6%). The patients underwent notochordal implantation (n = 27, 45%), quadrangular or triangular resection (n = 23, 38.3%), isolated ring annuloplasty (n = 7, 11.7%), resection, and leaflet reduction (n = 2, 3.3%) or edge to edge repair (n = 1, 1.7%). The maturation of the learning curve appeared to be about 30 cases. The statistical analysis showed that the mean CPB and CC times for the first 30 cases were greater compared with the 30 after learning curve (155.3 vs. 118.9 min [p = .00], 102.3 vs. 80 min [p = .00], respectively). There was no case of conversion to open surgery. No perioperative mortality was observed. CONCLUSION: The maturation of the learning curve for robotic-assisted MV repair appeared to be about 30 cases in our group of patients. This study had encouraging results for surgeons who desire to start a robotic mitral surgery program.

Easily measurable, noninvasive, and novel finding for pulmonary hypertension: Hypertrophy of the basal segment of septomarginal trabeculation of right ventricle.

BACKGROUND: Effect of pulmonary hypertension (PH) on right ventricular (RV) geometry constitutes an ideal target to assess both pulmonary artery pressure (PAP) and its physiological importance. In this study, we evaluated the diagnostic power of the basal segment of septomarginal trabeculation (SMT) in predicting the PH and RV hypertrophy by cardiovascular magnetic resonance (CMR) in patients with idiopathic pulmonary arterial hypertension (IPAH) and Eisenmenger's syndrome (ES). METHODS: Eleven patients with IPAH, seven patients with ES, and 20 healthy controls were enrolled. CMR was used to measure the area and the thickness of the basal segment of SMT and right ventricular free wall (RVFW). Pulmonary artery systolic pressures (PASPs) were estimated by transthoracic echocardiography (TTE) with continuous-wave Doppler analysis measuring maximal tricuspid regurgitation (TR) velocity. Late gadolinium enhancement (LGE) findings of CMR and brain natriuretic peptide (BNP) levels were also obtained in all patients and control group. RESULTS: The area and the thickness of the basal segment of SMT were higher in patients with IPAH and ES than control group (P<.001). Pulmonary artery dimension, end-diastolic diameter of RV, RVFW thickness, and BNP levels were found to be significantly correlated with PAP (P<.001). LGE was present at the insertion point of RV only in patients group (P<.001). CONCLUSIONS: Increased area and thickness of the basal segment of SMT are easily measurable noninvasive markers of PH in patients with IPAH and ES.

Transradial catheterization may decrease the radial artery luminal diameter and impair the vasodilatation response in the access site at late term: an observational study.

The present study aimed to evaluate the late-term changes in radial artery luminal diameter (RAD) and vasodilatation response following transradial catheterization (TRC). TRC-inducing trauma to radial artery intima may trigger chronic phase vascular changes and lead to anatomical and functional impairment. There is controversial data whether the impairment persists or repairs later. Fifty-six consecutive patients undergoing TRC were enrolled prospectively. Baseline RAD, flow-mediated dilatation (FMD) and nitroglycerin-mediated dilatation (NMD) of the radial artery at the access site were measured before TRC by high-resolution ultrasound. Six months later; RAD, FMD and NMD were measured again at the same access site. RAD at the sixth month was reduced compared with pre-procedural measurements (2.85 ± 0.44 versus 2.74 ± 0.42 mm, p = 0.0001).The average FMD decreased to 5.66 ± 5.87 %, which was significantly lower than the observed pre-procedural FMD (9.45 ± 5.01 %) 6 months after TRC (p = 0.0001). Likewise, the average NMD at the sixth month was reduced compared with pre-procedural NMD (9.52 ± 6.77 versus 6.64 ± 6.51 %, p = 0.018). Logistic regression analysis indicated that pre-procedural radial artery diameter to sheath size ratio was the independent predictor of NMD reduction (95 % confidence interval, ß = -9.74, p = 0.024). TRC may lead to a significant luminal diameter reduction and impairment of vasodilatation response in the radial artery at late term.

Comparison of Effects of Low- versus High-Dose Heparin on Access-Site Complications during Transradial Coronary Angiography: A Double-Blind Randomized Study.

OBJECTIVES: Although heparin is highly effective in reducing the rate of radial artery occlusion after transradial catheterization, the optimal heparin dose is still controversial. The aim of this study was to evaluate the efficacy and safety of two different heparin doses during transradial coronary angiography. METHODS: 490 consecutive patients undergoing transradial coronary angiography were prospectively enrolled into this double-blind randomized trial. A total of 202 patients enrolled in the low-dose (LD; 2,500 U of heparin) group and 202 patients enrolled in the high-dose (HD; 5,000 U of heparin) group were included in the final analysis. The primary endpoint of the study was radial artery occlusion. Bleeding and hematomas were the secondary outcome measures. RESULTS: At day 7, radial artery occlusion occurred in 5.9% of the patients in the LD group and in 5.4% of the patients in the HD group (p = 0.83). Bleeding during deflation of the transradial band occurred in 6.4% of the patients in the LD group and in 18.3% of the patients in the HD group; the difference was statistically significant (p < 0.001). Higher-dose heparin was found to be an independent predictor of bleeding (p = 0.007). CONCLUSION: A lower dose of heparin (i.e. 2,500 U) decreases bleeding during transradial band deflation without an increase in radial artery occlusion.

The relationship between epicardial adipose tissue and ST-segment resolution in patients with acute ST-segment elevation myocardial infarction undergoing primary percutaneous coronary intervention.

The relationship between epicardial adipose tissue (EAT) and coronary artery disease has been predominantly demonstrated in the last two decades. The aim of this study was to investigate the predictive value of EAT thickness on ST-segment resolution that reflects myocardial reperfusion in patients undergoing primary percutaneous coronary intervention (pPCI) for acute ST-segment elevation myocardial infarction (STEMI). The present study prospectively included 114 consecutive patients (mean age 54 ± 10 years, range 35-83, 15 women) with first acute STEMI who underwent successful pPCI. ST-segment resolution (ΔSTR) <70 % was accepted as ECG sign of no-reflow phenomenon. The EAT thickness was measured by two-dimensional echocardiography. EAT thickness was increased in patients with no-reflow (3.9 ± 1.7 vs. 5.4 ± 2, p = 0.001). EAT thickness was also found to be inversely correlated with ΔSTR (r = -0.414, p = 0.001). Multivariate logistic regression analysis demonstrated that EAT thickness independently predicted no-reflow (OR 1.43, 95 % CI 1.13-1.82, p = 0.003). Receiver operating characteristic curve analysis demonstrated good diagnostic accuracy for EAT thickness in predicting no-reflow [area under curve (AUC) = 0.72, 95 % CI 0.63-0.82, p < 0.001]. In conclusion, increased EAT thickness may play an important role in the prediction of no-reflow in STEMI treated with pPCI.

Carotid endarterectomy using a "home-constructed" shunt for patients intolerant to cross-clamping.

PURPOSES: There is a small minority of patients with occlusive carotid artery disease, who are at high-risk for general anesthesia because of their intolerance to carotid flow blockage, even if only for seconds, without neurologic deficit. Even <30 s of temporary clamping of the carotid arteries to deploy a shunt may prove eventful in this patient group. We define safe carotid endarterectomy after the insertion of a novel shunt that we made from simple medical equipment in this patient population. METHODS: Among 65 patients who underwent carotid endarterectomy between March 2010 and December 2012, 5 (7.7 %; 3 men and 2 women; age range 56-77 years) could not tolerate carotid clamping. We used an alternative carotid shunt, made by us from simple equipment in our clinic, during surgery for these patients. RESULTS: Two patients had bilateral lesions and the remainder had unilateral disease. The degree of stenosis ranged from 70 to 95 %. Temporary carotid clamping resulted in neurologic events, such as loss of consciousness in all and tremor in one, in <10 s (range, from immediately to 8 s after clamping). Full neurologic function was regained 15-30 s after releasing the clamps. All of the patients tolerated the procedures well with the support of our novel shunt. Shunt flow was adequate in all patients and no neurologic deterioration occurred after carotid clamping. The mean carotid clamp time was 28.11 ± 14.19 min. There was no mortality and all patients were followed up for a mean period of 9.3 ± 3.6 months, uneventfully. CONCLUSIONS: An alternative, simple shunt, which is easily constructed in the operating room or clinic, using an angiocatheter, a three-way stopcock, and a serum line can provide adequate cerebral flow and permit safe carotid endarterectomy for those rare patients with carotid artery stenosis, who cannot tolerate even seconds of carotid occlusion.

Pressure-controlled mechanical ventilation is more advantageous in the follow-up of patients with chronic obstructive pulmonary disease after open heart surgery.

OBJECTIVE: Cardiopulmonary bypass deteriorates pulmonary functions to a certain extent. Patients with chronic obstructive pulmonary disease (COPD) are associated with increased mortality and morbidity risks in the postoperative period of open-heart surgery. In this study we compared 2 different mechanical ventilation modes, pressure-controlled ventilation (PCV) and volume-controlled ventilation (VCV), in this particular patient population. PATIENTS AND METHODS: Forty patients with severe COPD were assigned to 1 of 2 groups and enrolled to receive PCV or VCV in the postoperative period. Arterial blood gases, respiratory parameters, and intensive care unit and hospital stays were compared between the 2 groups. RESULTS: Maximum airway pressure was higher in the VCV group. Pulmonary compliance was lower in the VCV group and minute ventilation was significantly lower in the group ventilated with PCV mode. The respiratory index was increased in the PCV group compared with the VCV group and with preoperative findings. Duration of mechanical ventilation was significantly shorter with PCV; however, intensive care unit and hospital stays did not differ. CONCLUSION: There is not a single widely accepted and established mode of ventilation for patients with COPD undergoing open-heart surgery. Our modest experience indicated promising results with PCV mode; however, further studies are warranted.

A rare manifestation of atrial fibrillation in the presence of Wolff-Parkinson-White syndrome: tachycardia-induced cardiomyopathy.

We report a 68-year-old man who presented with heart failure and atrial fibrillation (AF) with rapid ventricular response and wide QRS complexes. Tachycardia-induced cardiomyopathy (TIC) due to persistent AF developing on the basis of Wolff-Parkinson-White (WPW) syndrome was considered. Signs and symptoms of heart failure improved with restoration of sinus rhythm. This case suggested that persistent AF in a patient with WPW syndrome is one of the rare causes of TIC.

A randomized trial of flow-mediated dilation to prevent radial artery spasm during transradial approach.

BACKGROUND: Although transradial approach has been increasingly preferred for percutaneous coronary interventions, radial artery spasm (RAS) is still one of the major disadvantages. Flow-mediated dilation (FMD) is a well-known method for assessing endothelial function through dilation. The aim of this study was to investigate the efficacy of prepuncture flow mediated dilation in preventing RAS during transradial approach. METHODS: The present study prospectively included 222 consecutive patients who underwent transradial coronary intervention. Patients were 1:1 randomized into two groups who underwent prepuncture FMD and who did not (FMD [+] and FMD [-], respectively). RESULTS: In FMD [+] group the incidence of RAS was lower (5.4% vs. 16.2%, P=0.009). Multivariate logistic regression analysis demonstrated that female sex, more than two catheter usage and transradial approach without prepuncture FMD independently predicted RAS (odds ratio [OR]=4.66, 95% confidence interval [CI]: 1.8-12.06, P=0.001, OR=5.73, 95% CI: 2.01-16.39, P=0.001, and OR=5.01, 95% CI: 1.74-14.48, P=0.003; respectively). However, access site crossover number was very low in both groups and not different between groups. CONCLUSIONS: Prepuncture FMD can significantly reduce RAS during transradial coronary interventions. Thus, prepuncture FMD can be used as a simple adjunctive method to prevent RAS.

Comparison of Pericardiocentesis in Post-Cardiac Surgery and Nonsurgical Patients with Pericardial Tamponade.

INTRODUCTION: There are several approaches for pericardiocentesis. However, there is no definite suggestion about puncture location after cardiac surgery. The purpose of this study is to examine whether there is any difference regarding puncture location during pericardiocentesis in postoperative cardiac tamponade comparing to nonsurgical cardiac tamponade. METHODS: We retrospectively analyzed patients who had undergone pericardiocentesis from August 2011 to December 2019. Patients were examined in two groups, nonsurgical and postsurgical, based on the etiology of pericardial tamponade. Clinical profiles, echocardiographic findings, and procedural outcomes were identified and compared. RESULTS: Sixty-eight pericardiocenteses were performed in this period. The etiology of pericardial effusion was cardiac surgery in 27 cases and nonsurgical medical conditions in 41 cases. Baseline demographic variables were similar between the surgical and nonsurgical groups. Loculated effusion was more common in the postsurgical group (48.1% vs. 4.9%, P<0.001). Maximal fluid locations were different between the groups; right ventricular location was more common in the nonsurgical group (36.6% vs. 11.1%, P=0.02), while lateral location was more common in the postsurgical group (12.2% vs. 40.7%, P=0.007). Apical drainage was more frequently performed in the postsurgical group compared to the nonsurgical group (77.8% vs. 53.7%, P=0.044). CONCLUSION: Apical approach as a puncture location can be used more frequently than subxiphoid approach for effusions occurred after cardiac surgery compared to nonsurgical effusions. Procedural success is prominent in this group and can be the first choice of treatment.

Endothelial nitric oxide synthase gene (T-786C) polymorphism in patients with slow coronary flow.

OBJECTIVES: In this study, we aimed to investigate the relationship between T-786C polymorphism of the endothelial nitric oxide synthase (eNOS) gene and slow coronary flow (SCF). STUDY DESIGN: A total of 56 patients with SCF but otherwise normal coronary arteries (mean age 48+/-9 years) and 37 controls with normal coronary angiograms (mean age 50+/-12 years) were enrolled in the study. Screening for the eNOS T-786C polymorphism was performed by restriction fragment length polymorphism methodology. RESULTS: In normal coronary artery and SCF groups, TT genotype frequency was 23 (62.2%) versus 22 (39.3%), TC heterozygote genotype frequency was 11 (29.7%) versus 30 (53.6%), and CC homozygote genotype frequency was 3 (8.1%) versus 4 (7.1%), respectively (P=0.07). In dominant model statistical analysis, total CC and CT genotype frequency in control and study groups was found to be 14 (37.3%) versus 34 (60.7%), respectively (P=0.025). A positive correlation was found between the mean thrombolysis in myocardial infarction frame count and C allele in patients with SCF (r=0.21, P=0.043). CONCLUSION: We concluded that the T-786C polymorphism of eNOS gene might be a risk factor for the SCF.

Transthoracic Doppler echocardiographic coronary flow imaging in identification of left anterior descending coronary artery stenosis in patients with left bundle branch block.

BACKGROUND: Conventional noninvasive methods have well-known limitations for the detection of coronary artery disease (CAD) in patients with left bundle branch block (LBBB). However, advancements in Doppler echocardiography permit transthoracic imaging of coronary flow velocities (CFV) and measurement of coronary flow reserve (CFR). Our aim was to evaluate the diagnostic value of transthoracic CFR measurements for detection of significant left anterior descending (LAD) stenosis in patients with LBBB and compare it to that of myocardial perfusion scintigraphy (MPS). METHODS: Simultaneous transthoracic CFR measurements and MPS were analyzed in 44 consecutive patients with suspected CAD and permanent LBBB. Typical diastolic predominant phasic CFV Doppler spectra of distal LAD were obtained at rest and during a two-step (0.56-0.84 mg/kg) dipyridamole infusion protocol. CFR was defined as the ratio of peak hyperemic velocities to the baseline values. A reversible perfusion defect at LAD territory was accepted as a positive scintigraphy finding for significant LAD stenosis. A coronary angiography was performed within 5 days of the CFR studies. RESULTS: The hyperemic diastolic peak velocity (44 +/- 9 cm/sec vs 62 +/- 2 cm/sec; P=0.01) and diastolic CFR (1.38 +/- 0.17 vs 1.93 +/- 0.3; P=0.001) were significantly lower in patients with LAD stenosis compared to those without LAD stenosis. The diastolic CFR values of <1.6 yielded a sensitivity of 100% and a specificity of 94% in the identification of significant LAD stenosis. In comparison, MPS detected LAD stenosis with a sensitivity of 100% and a specificity of 29%. CONCLUSIONS: CFR measurement by transthoracic Doppler echocardiography is an accurate method that may improve noninvasive identification of LAD stenosis in patients with LBBB.

Application of cryoablation for the treatment of atrial fibrillation in patients undergoing cardiac surgery: Our mid-term results.

BACKGROUND: In this study, we aimed to present mid-term results of concomitant argon-based cryoablation in patients undergoing cardiac surgery. METHODS: Between August 2014 and May 2016, 33 patients (17 males, 16 females; mean age 63.9 years; range 45 to 82 years) underwent the Maze procedure using cryoablation for the treatment of atrial fibrillation during a concomitant open cardiac operation. Robot-assisted procedures were used in 12 patients. Biatrial or isolated left atrial ablation was performed according to the underlying pathology. The rhythm assessment with 12-lead electrocardiography and 24-hour Holter, and recordings of atrial fibrillation-related medications, stroke or other thromboembolic events were evaluated by the cardiologist at 3 and 12 months postoperatively. RESULTS: Thirty patients (90.9%) were in sinus rhythm and three (9.1%) were in atrial fibrillation at the time of discharge. Cryoablation failed in three patients (n=2, 8.3% in isolated left atrial and n=1, 11.1% in biatrial group) following the operation in the mid-term. Among the patients, there was no in-hospital mortality and no major postoperative complications such as stroke, sepsis, renal failure requiring dialysis, and prolonged respiratory failure. CONCLUSION: Concomitant surgical cryoablation is an effective method for the treatment of atrial fibrillation, when performed concomitantly with other cardiac surgical procedures and results in very low atrial fibrillation recurrence, even in robotic surgery.

Can radial artery pulse grading predict radial artery spasm during transradial approach?

BACKGROUND: Radial artery spasm (RAS) has been defined as one of the major disadvantage of transradial approach. AIM: The aim of this study was to investigate the predictive value of radial artery pulse grading on RAS during transradial approach. METHODS: The present study prospectively included 115 consecutive patients who underwent transradial coronary catheterisation at a single centre. Patients were divided into two groups: those with RAS and those without. RESULTS: The incidence of RAS was 16.5% (n = 19). Multivariate logistic regression analysis demonstrated that female sex, guiding catheter usage, and radial artery pulse grading ≤ 2 independently predicted RAS (odds ratio [OR] 8, 95% confidence interval [CI] 1.8-36.2, p = 0.007, OR 10.6, 95% CI 2.2-51.2, p = 0.03 and OR 25.8, 95% CI 6.1-108.5, p < 0.001, respec-tively). These three variables were weighted proportionally to their respective OR for RAS (female sex [1.5 points], guiding catheter usage [2 points], and radial artery pulse grading ≤ 2 [5 points]). Two risk strata were defined (low risk, score 0-4, high risk, score 5-8.5), and high risk was associated with increased incidence of RAS (n = 13 [61.9%] vs. n = 6 [6.4%], p < 0.001). CONCLUSIONS: Radial artery pulse grading together with female sex and guiding catheter usage are independent predictors of RAS, and by using a simple risk score high-risk patients for RAS can be identified.

Catheter entrapment due to severe radial artery spasm during transradial approach.

BACKGROUND: Catheter entrapment due to severe radial artery spasm (RAS) during transradial coronary catheterization has been rarely reported and its management is not precisely defined. The aim of this study was to determine the incidence, predictors and management of catheter entrapment due to severe RAS. METHODS: A total of 723 patients undergoing transradial coronary catheterization at a single center were retrospectively enrolled in the present study. Patients were divided into two groups: those with catheter entrapment due to severe RAS and those without. RESULTS: The incidence of catheter entrapment was 0.8%. Height (161.2 ± 9.1 cm vs. 169.6 ± ± 10 cm, p = 0.047) and body surface area (1.86 ± 0.04 vs. 1.95 ± 0.18, p = 0.002) were found to be lower, and total procedure time 33.2 ± 13.4 min vs. 15.2 ± 12.3 min, p < 0.001) was longer in the entrapment group. Multivariate logistic regression analysis demonstrated that total procedure time independently predicted catheter entrapment (odds ratio: 1.057, 95% confidence interval [CI] 1.004-1.114, p = 0.035). Receiver-operating characteristic curve demonstrated good diagnostic accuracy for prolonged total procedure time in predicting catheter entrapment (area under curve = 0.8, 95% CI 0.63-0.97, p = 0.01). Patients were effectively treated with stepwise administration of systemic vasodilators, forearm heating, sedation and as a last resort general anesthesia with no significant complication. CONCLUSIONS: Catheter entrapment due to severe RAS during transradial approach was rare and prolonged total procedure time is an independent predictor of catheter entrapment. Treatment with stepwise administration of different treatment modalities is possible with no significant complication.

Clinical usefulness of red cell distribution width to angiographic severity and coronary stent thrombosis.

BACKGROUND: Red cell distribution width (RDW) is a quantitative measurement and shows heterogeneity of red blood cell size in peripheral blood. RDW has recently been associated with cardiovascular events and cardiovascular diseases, and it is a novel predictor of mortality. In this study, we aimed to evaluate the clinical usefulness of measuring RDW in patients with coronary stent thrombosis. PATIENTS AND METHODS: We retrospectively reviewed 3,925 consecutive patients who presented with acute coronary syndrome and who underwent coronary angiography at the Siyami Ersek Hospital between May 2011 and December 2013. Of the 3,925 patients, 73 patients (55 males, mean age 59±11 years, 55 with ST elevated myocardial infarction) with stent thrombosis formed group 1. Another 54 consecutive patients who presented with acute coronary syndrome (without coronary stent thrombosis, 22 patients with ST elevated myocardial infarction, 44 males, mean age 54±2 years) and underwent percutaneous coronary intervention in May 2011 formed group 2. Data were collected from all groups for 2 years. The RDW values were calculated from patients 1 month later at follow-up. Syntax scores were calculated for all the patients. The patients were also divided as low syntax score group and moderate-high syntax score group. RESULTS: The patients in group 1 with stent thrombosis had significantly higher RDW level (13.85) than the patients in group 2 without stent thrombosis (12) (P<0.001). In addition, in all study patients, the moderate-high syntax score group had significantly higher RDW level (13.6) than the low syntax score group (12.9) (P=0.009). A positive correlation was determined between RDW and syntax scores (r=0.204). CONCLUSION: RDW is a new marker of poor prognosis in coronary artery disease. Increased RDW level is correlated with angiographic severity of coronary artery disease, and RDW may be an important clinical marker of coronary stent thrombosis in patients undergoing coronary intervention.

The Association between Subclinical Hypothyroidism and Epicardial Adipose Tissue Thickness.

BACKGROUND AND OBJECTIVES: Subclinical hypothyroidism (SH) is considered to be a potential risk factor for cardiovascular disease. Epicardial adipose tissue (EAT) thickness is also closely related to cardiovascular disorders. The aim of this study was to evaluate whether SH is associated with higher EAT thickness. SUBJECTS AND METHODS: Fifty-one consecutive patients with SH and 51 healthy control subjects were prospectively enrolled into this trial. Thyroid hormone levels, lipid parameters, body mass index, waist and neck circumference, and EAT thickness measured by echocardiography were recorded in all subjects. RESULTS: Mean EAT thickness was increased in the SH group compared to the control group (6.7±1.4 mm vs. 4.7±1.2 mm, p<0.001). EAT thickness was shown to be correlated with thyroid stimulating hormone level (r=0.303, p=0.002). Multivariate logistic regression analysis revealed that EAT thickness was independently associated with SH {odds ratio (OR): 3.87, 95% confidence interval (CI): 1.92-7.78, p<0.001; OR: 3.80, 95% CI: 2.18-6.62, p<0.001}. CONCLUSION: Epicardial adipose tissue thickness is increased in patients with SH compared to control subjects, and this increase in EAT thickness may be associated with the potential cardiovascular adverse effects of SH.

The effect of mild left ventricular diastolic dysfunction on outcome after isolated coronary bypass surgery.

BACKGROUND: Although moderate to severe diastolic dysfunction (DD) seems to be associated with poor prognosis after isolated coronary bypass surgery, the impact of mild DD has not been investigated extensively in this group of patients. AIM: We evaluated the prognostic implication of mild left ventricular (LV) DD on outcome after isolated coronary bypass surgery in patients with preserved LV systolic function. METHODS: Data from 650 patients undergoing isolated coronary bypass surgery and having records for LV diastolic function between January 2009 and August 2011 was collected retrospectively. DD was classified as mild (grade 1, impaired relaxation), moderate (grade 2, decreased compliance) or severe (grade 3-4, restrictive pattern) depending on mitral inflow wave, tissue Doppler imaging, and pulmonary vein flow wave. Patients with baseline rhythm other than sinus, moderate or severe valvular dysfunction, moderate or severe diastolic dysfunction, and LV ejection fraction lower than 50% were excluded. A total of 472 patients were identified within the database fulfilling the eligibility criteria for this analysis and stratified according to the echocardiographic findings as follows: group 1 comprised patients with normal diastolic function (n = 168); and group 2 was made up of patients with mild DD (impaired relaxation) (n = 304). These groups were compared for perioperative morbidity and mortality. RESULTS: The preoperative variables were comparable between groups. The outcome parameters of group 1 was similar compared to group 2 in terms of need for inotropic support (20.2% vs. 16.2%), intra-aortic balloon pump usage (0% vs. 1.4%), mechanical ventilation time (8.94 ± 0.96 h vs. 10.0 ± 0.89 h), reintubation rate (1.8% vs. 1.4%), intensive care unit stay time (24.1 ± 1.4 hvs. 26.2 ± 1.9 h), postoperative renal failure rate (0% vs. 0.3%), postoperative atrial fibrillation rate (10.1% vs. 11.2%), length of hospital stay (7.19 ± 0.45 vs. 6.57 ± 0.14 days), hospital readmission rate (3.1% vs. 3.1%), and mortality (0% vs. 1.6%). CONCLUSIONS: The results from this study indicate that mild LV DD is not associated with adverse outcome after coronary bypass surgery in patients with preserved LV systolic function, thus should not be considered as a preoperative risk factor.