Predictors of early outcome after coronary artery surgery in patients with severe left ventricular dysfunction

In-hospital mortality of patients with severe left ventricular dysfunction undergoing coronary artery bypass grafting in Iranian population

Background

Historically, coronary artery bypass grafting is associated with a higher mortality rate in patients with severe heart failure. This study aimed to assess the in-hospital mortality of CABG in patients with severe heart failure in Iranian patients and to identify factors associated with adverse outcomes.

Methods

This retrospective descriptive study enrolled patients with severe heart failure who underwent coronary artery bypass surgery from 2015 to 2020 in Madani Hospital, affiliated with Tabriz University of Medical Sciences.

Results

A total of 865 consecutive patients with a mean age of 60.65 ± 10.00 were enrolled in the study. Of all participants, 175 were female (20.4%), and 684 were male. The overall mortality rate was 9.5%. In the univariate analysis, predictors of ICU mortality were age, female sex, DM, and renal failure (P value < 0.05). None of the factors studied was an independent predictor of ICU mortality in the multivariate analysis.

Conclusion

This study established that although coronary artery bypass surgery is reported to have low mortality and postoperative morbidity in patients with severe heart failure, there are still centers that face higher mortality rates in these patients. Improving these patients' outcomes would be possible through identifying the associated risk factors and pre-and postoperative management.

Effects of trehalose on recurrence of remodeling after ventricular reconstruction in rats with ischemic cardiomyopathy

Recurrence of left ventricular (LV) remodeling after surgical ventricular reconstruction (SVR) for ischemic cardiomyopathy has been reported to be partially attributed to autophagy. We aimed to examine the effects of trehalose, an autophagy inducer, on the recurrence of LV remodeling after SVR. After SVR in rats with ICM, trehalose was orally administered. The changes in LV end-diastolic dimension (LVEDD) and fractional shortening (FS) were evaluated. The activation of myocardial autophagy was also estimated by autophagy markers: microtubule-associated light chain 3 II (LC3-II) and p62; the former usually increases and the latter decreases if autophagy is activated. Significant LV reverse remodeling was observed early after SVR. On the other hand, the 28th postoperative day SVR + trehalose was associated with smaller LVEDD and better FS than SVR alone (LVEDD, P = 0.043; FS, P < 0.01). LC3-II increased comparably in both groups, while p62 was significantly lower in the SVR + trehalose group than in the SVR alone group (P < 0.01). In conclusion, trehalose attenuated the recurrence of LV remodeling and changed autophagy markers after SVR in rats with ICM. Trehalose may be a candidate for adjuvant therapy to retain the effects of SVR.

Impact of left ventricular remodelling on outcomes after left ventriculoplasty for ischaemic cardiomyopathy: Japanese surgical ventricular reconstruction group experience

OBJECTIVES

Surgical ventricular reconstruction (SVR) for patients with severe left ventricular (LV) remodelling due to ischaemic cardiomyopathy is still controversial, because the Surgical Treatment for Ischaemic Heart Failure (STICH) trial demonstrated that SVR not only has no beneficial effect on survival compared with coronary artery bypass grafting (CABG) alone, but also is worse for those with a larger LV. Therefore, we assessed the impact of LV remodelling on the outcomes after SVR for ischaemic cardiomyopathy in Japan, using Di Donato's LV shape classification.

METHODS

From 2000 to 2010, 627 patients underwent SVR for ischaemic heart failure in 11 Japanese hospitals. To assess the patients with an LV ejection fraction (LVEF) of ≤ 35% like the STICH trial, considering the severity of LV remodelling, the patients with a preoperative LVEF of >35%, no preoperative LV volume assessment and no preoperative LV shape classification were excluded. Finally, 323 patients were selected as the study subjects. The LV shape was divided into three types according to Di Donato's classification. Types 1 and 3 indicate the aneurysmal and globally akinetic LV, respectively. Type 2 is the intermediate shape.

RESULTS

Type 1, 2 and 3 LV shapes were observed in 85 (26%), 104 (32%) and 134 (42%) of the patients, respectively. The preoperative LV volume and diameter increased if the LV became more akinetic (Type 3 > 2 > 1, P < 0.001). LVEF was lower in those with more akinetic LV (P = 0.002). The preoperative LV end-diastolic volume index and LVEF in Type 3 patients were 133 ± 47 ml/m(2) and 22 ± 7%, respectively. Mitral valve repair was more frequently performed for patients with the Type 3 LV shape (65%) than for the others (P < 0.001). The hospital mortality rates were 2.4, 2.9 and 7.4% for Type 1, 2 and 3 patients, respectively (P = 0.16). Kaplan-Meier analysis demonstrated no significant difference in mortality among the three groups (log-rank P = 0.37). The 5-year survival rates were 81, 70 and 73% for Type 1, 2 and 3 patients, respectively.

CONCLUSIONS

The severity of LV remodelling did not affect survival after SVR plus CABG. The results of SVR were acceptable even for those with globally akinetic LV due to ischaemic cardiomyopathy.

Tissue Doppler in critical illness: a retrospective cohort study

BACKGROUND

There is a paucity of published data on tissue Doppler imaging (TDI) in the critically ill. In a critically ill cohort, we studied the distribution of TDI and its correlation with other echocardiographic indices of preload. To aid hypothesis generation and sample size calculation, associations between echocardiographic variables, including the ratio of peak early diastolic transmitral velocity (E) to peak early diastolic mitral annular velocity (E'), and mortality were also explored.

METHODS

This retrospective study was performed in a combined medical/surgical, tertiary referral intensive care unit. Over a 2-year period, 94 consecutive patients who underwent transthoracic echocardiography with E/E' measurement were studied.

RESULTS

Mean Acute Physiology and Chronic Health Evaluation III score was 72 +/- 25. Echocardiography was performed 5 +/- 6 days after intensive care unit admission. TDI variables exhibited a wide range (E' 4.7-18.2 cm/s and E/E' 3.3 to 27.2). E' below 9.6 cm/s was observed in 63 patients (rate of myocardial relaxation below lower 95% confidence limit of normal individuals). Fourteen patients had E/E' above 15 (evidence of raised left ventricular filling pressure). E/E' correlated with left atrial area (r = 0.27, P = 0.01) but not inferior vena cava diameter (r = 0.16, P = 0.21) or left ventricular end-diastolic volume (r = 0.16, P = 0.14). In this cohort, increased left ventricular end-systolic volume, but not E/E', appeared to be an independent predictor (odds ratio 2.1, P = 0.007) of 28-day mortality (31%; n = 29).

CONCLUSION

There was a wide range of TDI values. TDI evidence of diastolic dysfunction was common. E/E' did not correlate strongly with other echocardiographic indices of preload. Further evaluation of echocardiographic variables, particularly left ventricular end-systolic volume, for risk stratification in the critically ill appears warranted.

Results and predictors of early and late outcome of coronary artery bypass grafting in patients with severely depressed left ventricular function

BACKGROUND

Coronary artery bypass grafting (CABG) is a well-accepted therapeutic approach in patients with symptomatic multivessel coronary artery disease and severely depressed left ventricular function. However, the potential impact of off-pump CABG in this group of patients remains unknown. In addition, there are only scarce data regarding long-term survival and its predictors in this patient population.

METHODS

We retrospectively analyzed prospectively collected data of 2,725 consecutive patients (mean age, 65 +/- 11 years; 843 (31%) female) undergoing CABG between January 1998 and December 2005 (ejection fraction [EF] < or = 0.30; n = 495, 18%). Outcome measures included hospital mortality, major complications, and long-term survival. Multivariate analysis was performed to identify predictors of hospital mortality and late survival. Subgroup analysis for patients with EF less than or equal to 0.30 undergoing conventional CABG (n = 424, 86%) versus off-pump CABG (n = 71, 14%) was performed.

RESULTS

Hospital mortality was 1.8% (EF < or = 0.30, 3.6%; EF > 0.30, 1.4%; p = 0.002). Off-pump CABG did not have an impact on operative mortality (on-pump, 4%; off-pump, 3%; p = 0.509). Ejection fraction of 0.30 or less was not an independent risk factor of hospital mortality but predicted respiratory failure (odds ratio [OR] = 2.3) and sepsis (OR, 1.4). Long-term survival was significantly decreased in patients with EF of 0.30 or less: 1-year and 5-year survival 88% +/- 1.5% and 75% +/- 2.2% versus 96% +/- 0.4% and 81% +/- 1.2%, respectively (p = 0.001). Reoperation (OR, 6.9), peripheral vascular disease (OR, 3.2), chronic obstructive pulmonary disease (OR, 3.0), congestive heart failure (OR, 2.7), and female sex (OR, 2.1) were independent predictors of long-term survival.

CONCLUSIONS

Excellent results after CABG can be expected in patients with EF of 0.30 or less, with minimal increase in mortality and acceptable postoperative morbidity. Long-term survival remains limited, but recent results are substantially better than historical reports. Careful preoperative patient selection and perioperative management are essential in these patients undergoing CABG.

Interleukin-1β increases expression and activity of matrix metalloproteinase-2 in cardiac microvascular endothelial cells: role of PKCα/β1and MAPKs

Matrix metalloproteinases (MMPs), a family of extracellular endopeptidases, are implicated in angiogenesis because of their ability to selectively degrade components of the extracellular matrix. Interleukin-1β (IL-1β), increased in the heart post-myocardial infarction (post-MI), plays a protective role in the pathophysiology of left ventricular (LV) remodeling following MI. Here we studied expression of various angiogenic genes affected by IL-1β in cardiac microvascular endothelial cells (CMECs) and investigated the signaling pathways involved in the regulation of MMP-2. cDNA array analysis of 96 angiogenesis-related genes indicated that IL-1β modulates the expression of numerous genes, notably increasing the expression of MMP-2, not MMP-9. RT-PCR and Western blot analyses confirmed increased expression of MMP-2 in response to IL-1β. Gelatin in-gel zymography and Biotrak activity assay demonstrated that IL-1β increases MMP-2 activity in the conditioned media. IL-1β activated ERK1/2, JNKs, and protein kinase C (PKC), specifically PKCα/β1, and inhibition of these cascades partially inhibited IL-1β-stimulated increases in MMP-2. Inhibition of PKCα/β1failed to inhibit ERK1/2. However, concurrent inhibition of PKCα/β1and ERK1/2 almost completely inhibited IL-1β-mediated increases in MMP-2 expression. Inhibition of p38 kinase and nuclear factor-κB (NF-κB) had no effect. Pretreatment with superoxide dismutase (SOD) mimetic, MnTMPyP, increased MMP-2 protein levels, whereas pretreatment with SOD and catalase mimetic, EUK134, partially inhibited IL-1β-stimulated increases in MMP-2 protein levels. Exogenous H2O2significantly increased MMP-2 protein levels, whereas superoxide generation by xanthine/xanthine oxidase had no effect. This in vitro study suggests that IL-1β modulates expression and activity of MMP-2 in CMECs.