Chronic atrial volume overload and atrial fibrillation (AF) induce structural changes within atrial myocardium. The aim of this study was to evaluate the effect of adverse cellular remodelling on echocardiographic strain rate (SR) deformation indices of atrial contractile, conduit and reservoir functions. Forty-four consecutive patients with organic mitral regurgitation were analysed. Twenty-eight patients had long-standing persistent AF (AF group), while 16 were in normal sinus rhythm (NSR group). Left atrial (LA) samples were harvested from all the patients for histological analysis. Postoperative echocardiographic data acquisition was performed exclusively during organized atrial electrical activity in order to assess the contractile reserve of patients from both groups. Fibrotic atria had inferior conduit (SR-E: r = −0.36, P = 0.017), reservoir (SR-S: r = −0.31, P = 0.041) and contractile functions (SR-A: r = −0.33, P = 0.027). Analogously, atria with greater apoptotic burdens showed a negative correlation with multiple indices of left atrial functions (SR-E: r = −0.38, P = 0.010; SR-S: r = −0.33, P = 0.028; SR-A: r = −0.28, P = 0.067). The efficiency of atrial contractility was significantly reduced among AF-group patients after conversion to sinus rhythm, when compared with patients in the NSR group (LA active emptying fraction: 20 ± 12 vs 30 ± 10%, P = 0.004; SR-A: 1.1 ± 1.0 vs 2.8 ± 1.9 s⁻¹, P < 0.001). Superior strain-rate indices of atrial conduit and reservoir functions were noted in the NSR group (SR-E: 3.5 ± 2.3 vs 1.3 ± 1.0 s⁻¹, P < 0.001; LA expansion index: 86 ± 31 vs 60 ± 42%, P = 0.004). Fibrosis was evident in 7.2 [3.3;9.4]% of the LA tissue sample in the AF group, while it accounted for 3.4 [1.2;8.1]% of atrial tissue in the NSR group (P = 0.054). Apoptosis was documented in 13 (46%) patients in the AF group, whereas none of the patients in the NSR group exhibited signs of programmed cell death (P = 0.001). Myocyte degeneration was more prevalent in the AF group (odds ratio: 7.0, 95% confidence interval: 1.3–36.7, P = 0.021). Age showed a positive correlation with worsening degrees of atrial fibrosis and apoptosis (r = 0.41, P = 0.006; r = 0.49, P = 0.001, respectively). Multiple regression analysis identified SR-S (β = −1.263, P = 0.036) and age (β = 0.144, P = 0.057) as independent predictors of fibrosis. Independent determinants of apoptosis were preoperative AF (β = 4.539, P = 0.007), age (β = 0.188, P = 0.009) and SR-S (β = −1.780, P = 0.002). Atria exhibiting greater fibrotic and apoptotic burdens had impaired conduit, reservoir and contractile function, as evaluated by deformation imaging. Among patients with chronic LA volume overload, exposure to long-standing persistent AF induced more pronounced degrees of adverse atrial cellular remodelling. Strain-rate descriptors of atrial reservoir function harboured potential to predict atrial fibrosis and apoptosis.

Coronary artery bypass grafting is pivotal in the contemporary management of complex coronary artery disease. Interpatient variability to antiplatelet agents, however, harbors the potential to compromise the revascularization benefit by increasing the incidence of adverse events. This study was designed to define the impact of dual antiplatelet therapy (dAPT) on clinical outcomes among aspirin-resistant patients who underwent coronary artery surgery. We randomly assigned 219 aspirin-resistant patients according to multiple electrode aggregometry to receive clopidogrel (75 mg) plus aspirin (300 mg) or aspirin-monotherapy (300 mg). The primary end point was a composite outcome of all-cause death, nonfatal myocardial infarction, stroke, or cardiovascular hospitalization assessed at 6 months postoperatively. The primary end point occurred in 6% of patients assigned to dAPT and 10% of patients randomized to aspirin-monotherapy (relative risk 0.61, 95% confidence interval 0.25 to 1.51, p = 0.33). No significant treatment effect was noted in the occurrence of the safety end point. The total incidence of bleeding events was 25% and 19% in the dAPT and aspirin-monotherapy groups, respectively (relative risk 1.34, 95% confidence interval 0.80 to 2.23, p = 0.33). In the subgroup analysis, dAPT led to lower rates of adverse events in patients with a body mass index >30 kg/m(2) (0% vs 18%, p <0.01) and those <65 years (0% vs 10%, p = 0.02). In conclusion, the addition of clopidogrel in patients found to be aspirin resistant after coronary artery bypass grafting did not reduce the incidence of adverse events, nor did it increase the number of recorded bleeding events. dAPT did, however, lower the incidence of the primary end point in obese patients and those <65 years.

Atrial fibrillation (AF) remains the most commonly observed complication following myocardial revascularisation surgery. We aimed to evaluate the clinical utility of N-terminal fragment of the brain natriuretic peptide (NT-pro-BNP), troponin T, transcoronary lactate gradient (TCLG) and C-reactive protein (CRP) as predictors of AF in patients undergoing isolated coronary artery bypass surgery (CABG). This study included 215 consecutive patients in sinus rhythm (SR) undergoing elective CABG between May 2007 and May 2008. The patients were grouped according to their respective postoperative rhythm into SR and AF groups. The data are presented as mean values+/-standard deviation, or medians with quartiles. Fifty-five patients developed AF (26%). The preoperative NT-pro-BNP values were 273+/-347 and 469+/-629 pg ml(-1) in the SR and AF groups, respectively (p<0.0001). The postoperative NT-pro-BNP values were 3110+/-3600 pg ml(-1) in the SR and 4625+/-5640 pg ml(-1) in the AF groups (p=0.027). The transcoronary lactate gradient rose from the pre-cardiopulmonary bypass values to those observed 5 min after revascularisation in both groups (-0.05+/-0.37 to 0.39+/-0.46 mmol l(-1) (p<0.0001) in the SR group and -0.01+/-0.27 to 0.43+/-0.46 mmol l(-1) (p<0.0001) in the AF group). The CRP values increased from 6+/-13 to 163+/-88 mg l(-1) (p<0.0001) in the SR group, and from 6+/-16 to 163+/-104 mg l(-1) (p<0.0001) in the AF group. The dynamics of TCLG and CRP did not differ between the groups (p=0.71, p=0.44, respectively). The troponin T values on postoperative day 1 were significantly higher in the AF than the SR group (0.86 (0.49-2.1) ng ml(-1) vs 0.67 (0.37-1.16) ng ml(-1), p=0.046). The duration of cardiopulmonary bypass (CPB) was 85+/-24 min in the SR and 93+/-30 min in the AF group (p=0.05). Patients who developed AF were older (66+/-7 years vs 60+/-9 years, p<0.0001) and had a higher EuroSCORE (3.9+/-2.7 vs 2.9+/-2.2, p=0.009). Multivariate analysis identified age (p=0.0043), preoperative NT-pro-BNP (p=0.019) and duration of CPB (p=0.035) as independent predictors of AF. Preoperative and postoperative NT-pro-BNP as well as TnT values were significantly higher in patients who subsequently developed AF. TCLG and CRP were not useful in identifying patients at higher risk for AF. Multivariate analysis identified age, preoperative NT-pro-BNP and duration of CPB as independent correlates of AF.

The advantage in terms of wound infection, wound healing, and scarring has resulted in the recent adoption of endoscopic vein harvesting (EVH) as a standard of care for coronary artery bypass grafting in some centers. However, concerns regarding the quality of these grafts have been raised after recent evidence of decreased graft patency, increased reoperation rate, and myocardial infarct, problems that are associated with vascular trauma caused when using this technique. Simultaneously, an atraumatic, “no-touch” technique for harvesting the saphenous vein was developed producing grafts with improved patency comparable to the internal thoracic artery. However, wound complications remain a problem using this technique. This review outlines the need to consider the poor graft quality that may result from EVH and raises the question what is likely to be the “best practice principle” in saphenous vein harvesting?