P-120 LAPAROSCOPIC REPAIR OF INCISIONAL HERNIA USING A NON-ABSORBABLE TRANSPARENT COMPOSITE PROSTHESIS TOTALLY IN POLYPROPYLENE - OUR EXPERIENCE

Introduction

Incisional ventral hernia is one of the most common surgical complications after laparotomy. The aim of this retrospective observational study is an evaluation of clinical outcomes after laparoscopic repair of incisional hernias with a non-absorbable and transparent composite prosthesis composed of a macro-porous monofilament polypropylene mesh and a transparent polypropylene film.

Materials and Methods

63 patients, from January 2016 to December 2021, were treated for incisional hernia at Center of minimal invasive surgery Nis, Serbia. The mesh was always positioned intraperitoneally after closing the defects and fixed with absorbable tacks and non-absorbable suture.

Results

In the considered cohort (54% female and 46% male) the median age and BMI were 54 years (range: 39–68) and 25,1 kg/m2 (range: 21.5–30.3), respectively. Concerning hernia position, 93.7% of the hernias were medial, 4.8% lumbar and 1.6% medio-lumbar. According to EHS classification, 58.7% of the hernias were W1, 36.5% W2 and 12.7% W3. The average duration of hospitalization was 2 days.

The rate of early post-operative complications was 6.3%, including 1 seroma (1.6%) and 3 patients reporting pain (4.8%). At a median follow up of 48 months (range: 6–60) we registered 2 cases of hernia recurrency (3.2%, both at 36 months follow-up) and 1 case of bowel obstruction (1.6%). All the considered variables did not result statistically significative in relation to post-operative complications.

Conclusion

Our clinical experience showed that intraperitoneal treatment of incisional hernia using a transparent composite prosthesis. The minimally invasive procedure allows a fast postoperative recovery and a consequent low economical cost.

Association between common cardiovascular risk factors and clinical phenotype in patients with hypertrophic cardiomyopathy from the European Society of Cardiology (ESC) EurObservational Research Programme (EORP) Cardiomyopathy/Myocarditis registry

AIMS

The interaction between common cardiovascular risk factors (CVRF) and hypertrophic cardiomyopathy (HCM) is poorly studied. We sought to explore the relation between CVRF and the clinical characteristics of patients with HCM enrolled in the EURObservational Research Programme (EORP) Cardiomyopathy registry.

METHODS AND RESULTS

1739 patients with HCM were studied. The relation between hypertension (HT), diabetes (DM), body mass index (BMI), and clinical traits was analysed. Analyses were stratified according to the presence or absence of a pathogenic variant in a sarcomere gene. The prevalence of HT, DM, and obesity (Ob) was 37, 10, and 21%, respectively. HT, DM, and Ob were associated with older age (P<0.001), less family history of HCM (HT and DM P<0.001), higher New York Heart Association (NYHA) class (P<0.001), atrial fibrillation (HT and DM P<0.001; Ob p = 0.03) and LV (left ventricular) diastolic dysfunction (HT and Ob P<0.001; DM P = 0.003). Stroke was more frequent in HT (P<0.001) and mutation-positive patients with DM (P = 0.02). HT and Ob were associated with higher provocable LV outflow tract gradients (HT P<0.001, Ob P = 0.036). LV hypertrophy was more severe in Ob (P = 0.018). HT and Ob were independently associated with NYHA class (OR 1.419, P = 0.017 and OR 1.584, P = 0.004, respectively). Other associations, including a higher proportion of females in HT and of systolic dysfunction in HT and Ob, were observed only in mutation-positive patients.

CONCLUSION

Common CVRF are associated with a more severe HCM phenotype, suggesting a proactive management of CVRF should be promoted. An interaction between genotype and CVRF was observed for some traits.

Relative impact of acute heart failure and acute kidney injury on short- and long-term prognosis of patients with STEMI treated with primary PCI

Background

Although both acute heart failure (AHF) and acute kidney injury (AKI) have been separately recognized as contributors to an increased mortality risk in patients with ST-segment elevation myocardial infarction (STEMI), their relative importance has not been extensively studied.

Purpose

Our aim was to investigate the relative impact of AHF and AKI on 30-day and 5-year mortality following primary PCI for STEMI.

Methods

8 054 patients referred to primary PCI during the years 2009–2019, and with the available repeated creatinine measurements, were analyzed. AKI was defined as ≥25% relative or ≥0.5 mg/dl absolute rise in creatinine from baseline, within 72 hours of intervention. Acute heart failure was defined as Killip class ≥2 on admission to hospital. Cox regression model was used to assess the effect of the interaction of AHF and AKI on mortality. Median follow-up was 5 years.

Results

The incidence of AKI was 9.9% (n=805) and of AHF 12.3% (n=1050). Concurrence of AHF and AKI was noted in 1.7% of the included patients (n=315). The combined presence of AHF and AKI significantly increased mortality both at 30 days (30.7%) and at 5 years (73.3%), as compared with AKI alone (8.2% at 30 days and 32.3% at 5 years) and AHF alone (13.0% and 53.0%). When adjusted for other significant predictors, such as age, prior stroke, hyperlipidemia, atrial fibrillation, ejection fraction, final TIMI flow in the culprit artery, the use of intra-aortic balloon pump and multivessel disease, both AKI and AHF were independently associated with mortality. The adjusted relative impact of AKI on mortality was stronger than that of AHF at 30 days (adjusted HR 3.5 and 2.2, respectively), whereas it was comparable at 5 years (adjusted HR 1.3 and 1.4, respectively). Furthermore, the combined presence of AHF on admission and the post-primary PCI development of AKI was associated with the highest magnitude of risk at both 30 days (HR 5.0, CI95% 3.0–8.3, p&lt;0.001) and 5 years (HR 2.4, CI95% 1.83–3.16, p&lt;0.001).

Conclusion

Acute kidney injury following primary PCI for STEMI was associated with a higher adjusted risk of short-term mortality when compared with acute heart failure, whereas their relative impact was comparable in the long-term.

Funding Acknowledgement

Type of funding sources: None.

Prognostic impact of elevated baseline CRP levels in primary PCI-treated patients with residual cholesterol risk

Background

Recent large randomized studies have indicated the potential of anti-inflammatory therapies to reduce adverse cardiovascular events in patients with myocardial infarction, with the most pronounced benefit in patients with baseline elevated C-reactive protein (CRP).

Purpose

Our aim was to assess the association of CRP levels with 30-day and 1-year mortality in patients with acute myocardial infarction treated with primary PCI and with residual cholesterol risk.

Methods

The study included 1531 patients admitted for primary PCI, with the residual cholesterol risk, i.e. low-density lipoprotein cholesterol (LDL-C) levels of &gt;1.80 mmol/l (70 mg/dl), from a prospectively kept electronic registry of a high-volume tertiary center, for whom in-hospital CRP measurements were available. Elevated CRP was defined as ≥5 mg/l (local laboratory cut off value), measured during index hospitalization. Cox regression models were constructed to assess the impact of elevated CRP on 30-day and 1-year mortality.

Results

72% of the included patients with LDL-C &gt;1.80 mmol/l had elevated in-hospital CRP (n=1107). Compared with patients with CRP levels within reference limit, elevated CRP was associated with older age (62 vs. 60, p&lt;0.001), higher rates of diabetes (25.8% vs. 18.5%, p=0.002), renal failure (6.4% vs. 2.1%, p&lt;0.001) and Killip class &gt;1 at presentation (22.5% vs. 12.3%, p&lt;0.001), as well as lower EF (44% vs. 48%, p&lt;0.001) and lower haemoglobin on admission (13.9 g/dl vs. 14.2 g/dl, p&lt;0.001). Crude mortality rates were increased in patients with CRP ≥5mg/l at both 30 days (6.0% vs. 2.4%, p=0.003) and 1 year (13.2% vs. 6.3%, p&lt;0.001) (Figure). After adjusting for the observed baseline differences, CRP ≥5mg/l remained an independent predictor of mortality at 1 year (HR 1.691, 95% CI: 1.050–2.724, p=0.03), but not at 30 days (HR 1.690, 95% CI: 0.859–3.324, p=0.13).

Conclusion

In primary PCI-treated patients with residual cholesterol risk, elevated in-hospital CRP was independently associated with 1-year mortality. Our findings may thus suggest a potential window of opportunity, for anti-inflammatory therapies to improve outcomes beyond the acute phase.

Figure 1

Funding Acknowledgement

Type of funding source: None

Characteristics, predictors and outcomes after unprotected left main stem primary percutaneous coronary intervention

Background

Reports about outcomes of patients undergoing primary percutaneous coronary intervention (PCI) for unprotected left main (ULM) coronary artery are limited. We aimed to investigate the characteristics, in-hospital and the long-term outcomes of these patients.

Methods

From a high-volume, single-centre, prospective registry, in a period from 2009–2019, we identified 111 pts (0.96%) who undergone primary PCI for ULM culprit lesion. The short- and the long-term outcomes in this subset was evaluated and compared to 9463 (82.5%) patients undergoing pPCI for lesions located in other segments (Non-LM group). Technical success was defined as final TIMI 3 flow in both, left main and distal vessels, anterior descending and circumflex artery, without significant residual stenosis (&gt;20% following balloon angioplasty or stent implantation) and side branch compromise (residual stenosis &gt;75%).

Results

Patients with ULM were older and more likely to present as Non-ST-elevation MI (77% vs. 93%; p&lt;0.000) and in cardiogenic shock (40% vs. 2.2%; p&lt;0.000), having less occlusive disease with TIMI 0–1 flow prior to PCI (44% vs. 78%; p&lt;0.000) compared to Non-LM patients. Also, greater procedure complexity was observed with longer lesions &gt;20mm (50% vs. 29%; p&lt;0.000), more intraluminal thrombus (86% vs. 45%; p&lt;0.000), greater number (1,48±0,9 vs. 1,28±0,7; p&lt;0.01) and longer stents (30,5±15,8 vs. 27,4±14,3; p=0.028), more GP IIb/IIIa inhibitors (32% vs. 23%; p=0.022), intra-aortic counterpulsations (7% vs. 0.6%; p&lt;0.000) and contrast media used (202±96 vs. 172±66; p&lt;0.000) in ULM group. Despite obtaining comparable rates of final TIMI 3 flow in main branch (91.9% vs. 95.4%; p=0.084), patients with LMCA had significantly higher in-hospital (27% vs. 4.7%: p&lt;0.000), and one-year all-cause mortality (41% vs. 11%: p&lt;0.000), but for the remaining duration of clinical follow-up (available for 97.8% pts, median duration 51±37 months) survival rates were comparable between ULM and Non-LM pts (18% vs. 15%: p=0.506) (Figure 1).

Regression analysis showed that final TIMI 3 in main branch at 30 days (HR 0.05 [95% CI 0.005–0.604]; p=0.018), while peri-procedural cardiogenic shock (hazard ratio (HR) 8.3 [95% CI 2.5–28.1]; p=0.001), creatinine clearance &lt;60 ml/min (HR 7.5 [95% CI 2.3–25.1]; p=0.001) and technical success (HR 0.16 [95% CI 0.45–0.57]; p=0.005) at 5 years, independently predicted mortality in ULM patients.

Conclusions

Despite performance of primary PCI, patients with MI due to ULM lesions are associated with worse in-hospital and one-year mortality but following that period mortality was comparable to control group. Suboptimal final coronary flow best predicted the 30 day, while peri-procedural cardiogenic shock, renal dysfunction at admission and suboptimal technical procedure result, predicted long-term mortality in these patients.

Figure 1

Funding Acknowledgement

Type of funding source: None

Clinical characteristics and long-term mortality of patients with midrange ejection fraction undergoing primary percutaneous coronary intervention for ST-elevation myocardial infarction

Background

Previous studies associated midrange ejection fraction (mrEF) with impaired prognosis in patients with ST-elevation myocardial infarction (STEMI).

Purpose

Our aim was to assess clinical profile and short- and long-term mortality of patients with mrEF after STEMI treated with primary percutaneous coronary intervention (PCI).

Methods

This analysis included 8148 patients admitted for primary PCI during 2009–2019, from a high-volume tertiary center, for whom echocardiographic parameters obtained during index hospitalization were available. Midrange EF was defined as 40–49%. Adjusted Cox regression models were used to assess 30-day and 5-year mortality hazard of mrEF, with the reference category being preserved EF (&gt;50%).

Results

mrEF was present in 29.8% (n=2 427), whereas low ejection fraction (EF&lt;40%) was documented in 24.7% of patients (n=2 016). mrEF was associated with a higher baseline risk as compared with preserved EF patients, but lower when compared with EF&lt;40%, in terms of prior MI (14.5% in mrEF vs. 9.9% in preserved EF vs. 24.2% in low EF, p&lt;0.001), history of diabetes (26.5% vs. 21.2% vs. 30.0%, p&lt;0.001), presence of Killip 2–4 on admission (15.7% vs. 6.9% vs. 26.5%, p&lt;0.001) and median age (61 vs. 59 vs. 64 years, p&lt;0.001). At 30 days, mortality was comparable in mrEF vs. preserved EF group, while it was significantly higher in the low EF group (2.7% vs. 1.6% vs. 9.4%, respectively, p&lt;0.001). At 5 years, mrEF patients had higher crude mortality rate as compared with preserved EF, but lower in comparison with low EF (25.1% vs. 17.0% vs. 48.7%, p&lt;0.001) (Figure). After adjusting for the observed baseline differences mrEF was independently associated with increased mortality at 5 years (HR 1.283, 95% CI: 1.093–1.505, p=0.002), but not at 30 days (HR 1.444, 95% CI: 0.961–2.171, p&lt;0.001).

Conclusion

Patients with mrEF after primary PCI for STEMI have a distinct baseline clinical risk profile, as compared with patients with reduced (&lt;40%) and preserved (≥50%) EF. Importantly, mrEF did not have a significant impact on short-term mortality following STEMI, but it did independently predict the risk of 5-year mortality.

Funding Acknowledgement

Type of funding source: None

Prognostic impact of gender and young age in patients with acute myocardial infarction undergoing primary PCI

Background

Previous studies showed higher unadjusted mortality rates in female patients with acute myocardial infarction (AMI) undergoing primary percutaneous coronary intervention (PCI). However, after adjusting for differences in baseline characteristics, including age, female gender was not consistently associated with higher mortality.

Purpose

Our aim was to investigate the impact of gender on short- and long-term mortality in patients aged 18 to 55 years with AMI undergoing primary PCI.

Methods

We included 11 288 patients admitted for primary PCI during 2009–2019, from a prospectively kept, electronic registry of a high-volume tertiary center. Adjusted Cox regression models were used to assess 30-day and 5-year mortality hazard. Median follow up was 1 507 days.

Results

3 505 patients were younger than 55 years (31%). In this age group, 18.9% were female patients (n=661). Baseline characteristics were similar for females vs. males below the age of 55 years, including similar reperfusion times (338 min. vs. 341 min., p=0.8), with only exceptions being a higher rate of previous hypertension (64% vs. 58%, p=0.002) and stroke (3.6% vs. 2.2%, p=0.049), as well as lower ejection fraction (48% vs. 51%, p&lt;0.001), in female patients. MINOCA (Myocardial Infarction with Nonobstructive Coronary Arteries) was more frequently present in female vs. male patients aged ≤55 years (10.1% vs. 5.0%, p&lt;0.001). In the overall population, crude mortality was higher in female patients at 30 days (9.8% vs. 6.0%, p&lt;0.001) and 5 years (38.4% vs. 30.2%, p&lt;0.001). In younger patients (≤55 years), mortality rates were low and similar between the sexes at both 30 days (3.6% in females vs. 2.5% in males, p=0.136) and 5 years (14.5% vs. 13.4%, p=0.58). On the contrary, in patients aged &gt;55 years, crude mortality was higher in female patients at both 30 days (11.3% vs. 7.9%, p&lt;0.001) and 5 years (43.9% vs. 39.4%, p=0.02), albeit mainly driven by the differences in baseline characteristics between the sexes in this older age group (adjusted HR for female sex 1.220, CI95% 0.920–0.617, p=0.17, at 30 days; and adjusted HR 1.033, CI95% 0.908–0.175, p=0.62, at 5 years).

Conclusion

Differences in crude mortality rates between sexes in patients with AMI admitted for primary PCI appear to be mainly dependent on age, with similar rates of both short- and long-term mortality in younger patients (≤55 years). The observed excess in mortality in older (&gt;55 years) female vs. male patients could be explained by the differences in baseline clinical characteristics.

Funding Acknowledgement

Type of funding source: None

Prognostic impact of atrial fibrillation in patients undergoing primary PCI with versus without left ventricular function impairment

Background

Atrial fibrillation (AF) and impaired left ventricular (LV) function have both been separately associated with increased risk of mortality following primary percutaneous coronary intervention (PCI) in patients with ST-elevation myocardial infarction (STEMI).

Purpose

Our aim was to comparatively evaluate the impact of LV dysfunction and AF on the risk of mortality in primary PCI-treated patients.

Methods

This analysis included 8561 patients admitted for primary PCI during 2009–2019, from a prospectively kept, electronic registry of a high-volume tertiary center, from whom echocardiographic parameters were available. LV dysfunction was defined as EF&lt;40%. Adjusted Cox regression models were used to assess 30-day and 1-year mortality hazard.

Results

AF was present in 3.2% (n=273), whereas 37% had LV dysfunction (n=3189). Crude mortality rates were increased in the presence of either AF or LV dysfunction, and were the highest in the group of patients having both AF and impaired LV function, at 30 days (1.8% in no AF and no LV dysfunction vs. 5.4% if AF only vs. 7.0% if EF&lt;40% only vs. 14.9% if AF and LV dysfunction concurrently present, p&lt;0.001) and at 3 years (10.5% if no AF and no LV dysfunction vs. 35.8% if AF only vs. 28.5% if EF&lt;40% only vs. 60.3% if AF and LV dysfunction both present, p&lt;0.001). After multivariable adjustment for other significant mortality predictors, including age, previous stroke, MI, diabetes, hyperlipidemia, anemia and Killip≥2, LV dysfunction alone and in combination with AF was an independent predictor of mortality at both 30 days (HR=2.2 and HR=2.5, respectively, p&lt;0.001 for both) and at 3 years (HR=1.9 and HR=2.9, respectively, p&lt;0.001 for both). However, presence of AF alone, in the absence of an impaired LV function, was not independently associated with mortality at 30 days (HR 1.34, CI 95% 0.58–3.1, p=0.48), but rather at 3 years (HR 1.74, CI 95% 1.91–2.54, p=0.004).

Conclusion

Atrial fibrillation is associated with long-term mortality in STEMI patients undergoing primary PCI, irrespective of the LV function. Conversely, short-term prognostic relevance of atrial fibrillation in STEMI is dependent on the presence of LV dysfunction.

Kaplan Meier curve_AF_LV dysfunction

Funding Acknowledgement

Type of funding source: None

Comparison of contrast induced nephropathy definitions and in-hospital mortality in patients undergoing primary percutaneous coronary intervention for acute myocardial infarction

Background

Contrast induced nephropathy (CIN) has been associated with increased mortality in patients with acute myocardial infarction (AMI). However, different definitions of CIN have so far been used.

Purpose

We aimed to compare predictive accuracy of the 2 contemporary CIN definitions in patients with AMI undergoing primary percutaneous coronary intervention (PCI).

Method

From a high-volume, single-centre, prospective registry, in a period from 2009–2019, we identified 7987 pts who underwent primary PCI for AMI in whom creatinine measurements were available for analysis. CIN incidence was evaluated according to relative creatinine increases of ≥25% (CIN25) and ≥50% (CIN50) from baseline levels within 72 hours after intervention. The primary end point was in-hospital mortality.

Results

Overall, 1116 (13.9%), and 345 (4.3%) patients developed CIN25, CIN50, respectively. Crude in-hospital mortality rate was 3.9% (312 pts) in the overall population. Both definitions were independently associated with in-hospital mortality (CIN25 adjusted odds ratio (OR) 4.2, 95% CI 2.7–6.6; p&lt;0.001, and CIN 50 adjusted OR 8.2, 95% CI 4.9–13.9; p&lt;0.001). Comparison of ROC curves showed that only the addition of the CIN50 (and not CIN25) definition to the combined model of clinical predictors of in-hospital mortality, which included pre-intervention TIMI flow 0–1, cardiogenic shock on admission, baseline creatinine clearance, prior stroke, chronic occlusion of non-culprit artery, post-intervention TIMI flow 3, left ventricular ejection fraction and procedure time, improved prognostic accuracy of the model (Figure 1).

Conclusion

Only acute kidney injury according to the CIN50 definition, but not the CIN25 definition, offers additional prognostic information above and beyond the combination of baseline predictors of in-hospital mortality in patients with AMI undergoing primary PCI.

Figure 1

Funding Acknowledgement

Type of funding source: None

Impact of a CTO in a non-infarct-related artery on long-term mortality in patients undergoing primary PCI

Background

Previous studies showed increased mortality rates in patients with ST-elevation myocardial infarction (STEMI) and a chronic total occlusion (CTO) in a non-infarct-related artery, but long-term data are scarce.

Purpose

Our aim was to assess all-cause mortality during 5 years follow-up in patients with a remaining nonculprit CTO after being treated with primary PCI.

Methods

The study included 9504 patients admitted for primary PCI during 2009–2019, with available baseline angiography, from an electronic, prospective registry of a high-volume catheterization laboratory. Kaplan Meier cumulative mortality curves for non-culprit CTO vs. no CTO were compared with the log-rank test, with landmarks set at 30 days and then annually up to 5 years follow-up. Adjusted Cox regression models were constructed to assess 30-day and 5-year mortality risk of a non-culprit CTO. Median follow-up was 1507 days.

Results

Nonculprit CTO was present in 13.2% of patients (n=1253). Presence of a nonculprit CTO was associated with older age (64 vs. 61, p&lt;0.001), more frequent history of cardiovascular disease including prior MI (33% vs. 14%, p&lt;0.001), stroke (10.3% vs. 5.9%, p&lt;0.001) and CABG (10.5% vs. 1.5%, p&lt;0.001), higher rates of renal failure (10.7% vs. 4.8%, p&lt;0.001), as well as more often Killip class 2–4 on admission (29% vs. 16%, p&lt;0.001) and a lower ejection fraction (40% vs. 47%, p&lt;0.001). Crude mortality rates were significantly increased in patients with a nonculprit CTO vs. no CTO, at both 30 days (15.7% vs. 5.6%, p&lt;0.001) and 5 years (54.6% vs. 27.9%, p&lt;0.001). After adjusting for the observed baseline differences, nonculprit CTO was still associated with an elevated mortality risk at both 30-days (HR 1.5, CI95% 1.1–1.9, p=0.007) and 5 years (HR 1.6, CI95% 1.4–1.9, p&lt;0.001). Landmark analyses showed continuously increasing risk of mortality in the presence of a nonculprit CTO, as compared with primary PCI-treated patients with no CTO (30 days to 1 year 11.4% vs. 4.9%, p&lt;0.001; 1st to 2nd year of follow-up 6.3% vs. 3.4%, p&lt;0.001; 2nd to 3rd year 6.2% vs. 2.8%, p&lt;0.001; 3rd to 4th year 7.4% vs. 3.0%, p&lt;0.001; and 4th to 5th year 5.2% vs. 3.6%, p=0.1).

Conclusions

Presence of a nonculprit CTO is independently associated with 5-year mortality after primary PCI. Importantly, the mortality risk increases continuously with an average annual absolute difference of 3%, in patients with a nonculprit CTO vs. those with no CTO.

Nonculprit CTO vs. no CTO

Funding Acknowledgement

Type of funding source: None

Comparison of the FASTEST and the ZWOLLE risk scores for identification of very low-risk patients for all-cause mortality and MACE following primary PCI

Background

Prior studies suggest that low-risk ST-segment-elevation myocardial infarction (STEMI) patients undergoing primary percutaneous coronary intervention (pPCI) can be considered for early discharge in order to reduce healthcare costs and improve resource utilization. Novel, simple, the FASTEST score, demonstrated additional prognostic value over guideline recommended ZWOLLE score in a derivation cohort, but robust data about external validation are lacking.

Purpose

We aimed to compare overall predictive ability and discriminating power in identification of low-risk patients of novel FASTEST score compared to validated ZWOLLE score.

Methods

From a high-volume, single-center, prospective registry, in a period from 2009–2019, we included STEMI patients who underwent successful pPCI in whom both, FASTEST (1 point added for: femoral access, age&gt;65, LVEF &lt;50, TIMI &lt;3, creatinine &gt;1.5 mg/dl; left main disease; and Killip≥2) and ZWOLLE (age, anterior infarct, Killip class, TIMI flow, ischemia time, 3 vessel disease) scores were both calculated. Predictive ability of scores for in-hospital, 30 days and 1 year mortality and hospital MACE was tested using ROC analysis and comparing AUC. Also, event rate was compared between low-risk patients as classified by FASTEST (score=0) or ZWOLLE (score≤3).

Results

We included 5650 patients (age 60.8±11.4, male (71%), anterior STEMI (44%) and femoral approach (81%)). Overall, mortality rates were 2.1%, 3.1% and 8.1% for hospital, 30 days and one-year. As Low-risk subjects, ZWOLLE identified broader proportion of population compared to FASTEST (67% vs. 5.5%) mainly due to high prevalence of femoral approach (FASTEST low-risk 30% in radial approach subset), still, later had numerically lower mortality rates at hospital (0.7% vs. 0.3% (only 1 pt); p=0.62), 30 days (1.3% vs. 0.7%; p=0.39) and at one-year (4% vs. 2%; p=0.14). Both scores showed similar and very good predictive ability for in-hospital (AUC 0.81 vs. 0.81; p=0.66) and 30 days mortality (AUC 0.79 vs. 0.77; p=0.29), while at one-year, discrimination of crude mortality by FASTEST trended, but didn't reach statistical significance compared to ZWOLLE score, respectively (AUC 0.77 vs. 0.75; p=0.07). FASTEST showed better prediction for composite endpoint of in-hospital MACE - death, stroke, reinfarction and bleeding BARC class 3 or higher (AUC 0.71 vs. 0.67; p&lt;0.000) (Figure 1).

Conclusion

Both the FASTEST and the ZWOLLE scores showed very good discriminating power for in-hospital, 30 day mortality and one-year mortality, yet the FASTEST score offered comparative advantage for prediction of in-hospital MACE and could be used to identify selected patients where an early hospital discharge can be considered.

ZWOLLE vs FASTEST ROC analisys

Funding Acknowledgement

Type of funding source: None

3269Impact of type 2 diabetes on incidence and phenotype of heart failure in patients with atrial fibrillation

Background

Type 2 diabetes (T2DM) portends adverse prognosis in patients with atrial fibrillation (AF). Whether T2DM independently increases the risk of incident heart failure (HF) in AF is uncertain. Also, HF phenotype developing in patients with vs. those without T2DM has not been characterised.

Purpose

In AF patients without a history of prior HF, we aimed to assess: 1) the impact of T2DM on the risk of new-onset HF; and 2) the association between T2DM and HF phenotype developing during the prospective follow-up.

Methods

We included diabetic and non-diabetic AF patients, without a history of HF. Baseline T2DM status was inferred from medical history, haemoglobin A1c levels and oral glucose tolerance test. Study outcome was the first hospital admission or emergency department treatment for new-onset HF during the prospective follow-up. The phenotype of new-onset HF was determined by echocardiographic exam performed following clinical stabilisation (at hospital discharge, or within a month after HF diagnosis). HF phenotype was defined as HFrEF (left ventricular ejection fraction [LVEF] <40%), HFmrEF (LVEF 40–49%) or HFpEF (LVEF≥50%). Cox regression analyses adjusted for age, sex, baseline LVEF, comorbidities, smoking status, alcohol intake, AF type (paroxysmal vs. non-paroxysmal) and T2DM treatment was used to analyse the association between T2DM and incident HF.

Results

Among 1,288 AF patients without prior HF (mean age: 62.1±12.7 years; 61% male), T2DM was present in 16.5%. Diabetic patients had higher mean baseline LVEF compared with nondiabetic patients (50.0±6.2% vs. 57.6±9.0%; P<0.001). During the median 5.5-year follow-up, new-onset HF occurred in 12.4% of patients (incidence rate, 2.9; 95% confidence interval [CI], 2.5–3.3 per 100 patient-years). Compared with non-diabetic patients, those with T2DM had a hazard ratio of 2.1 (95% CI, 1.6–2.8; P<0.001) for new-onset HF, independent of baseline LVEF or other factors. In addition, diabetic patients had a significantly greater decline in covariate-adjusted mean LVEF (−10.4%; 95% CI, −9.8% to −10.8%) at follow-up, compared with nondiabetic patients (−4.0%; 95% CI, −3.8% to −4.2%), P<0.001. The distribution of HF phenotypes at follow-up is presented in Figure. Among patients with T2DM, HFrEF (56.9%) was the most common phenotype of HF, whereas in patients without T2DM, HF mostly took the phenotype of HFpEF (75.0%).

Conclusions

T2DM is associated with an independent risk of new-onset HF in patients with AF and confers a greater decline in LVEF compared to individuals without T2DM. HFrEF was the most prevalent presenting phenotype of HF in AF patients with T2DM.

P4619Comparison of the CRUSADE, ACUITY-HORIZONS, and ACTION bleeding risk scores for predicting in-hospital bleeding in acute myocardial infarction patients undergoing primary PCI

Background

Considering clinical importance of bleeding complications in patients with acute myocardial infarction (AMI), bleeding risk stratification is a key part of the management of these patients. CRUSADE, ACTION and ACUITY-HORIZONS bleeding risk scores are available for predicting in-hospital major bleeding events in patients with acute myocardial infarction.

Purpose

We aimed to evaluate performance of the three above mentioned risk scores for predicting in-hospital bleeding events defined according to The Bleeding Academic Research Consortium (BARC) criteria.

Methods

From a prospective electronic registry of a high-volume catheterization laboratory in a period from January 2009 to December 2017, a total of 6505 consecutive patients with acute myocardial infarction who underwent pPCI were included in analysis. Calibration and discrimination of the three risk models were evaluated by the Hosmer-Lemeshow (H-L) goodness-of-fit test and C-statistic, respectively.

Results

Overall there were 372 (5.7%) bleeding events out of which 117 (1.8%) fulfilled stage BARC 3 or higher bleeding criteria. All three scores showed good model calibration as assessed by the H-Ls test and very good discriminative power for BARC 3 of higher bleeding events detection as assessed by C-statistics (Table 1 & Figure 1):

Bleeding events stage BARC 3 or higher were statistically highly related with higher in-hospital mortality (13.7% vs. 3.5%; p<0.000).

Table 1 Risk score H-L H-L p AUC 95% CI p CRUSADE 11.46 0.177 0.761 0.750–0.771 vs. ACUITY = ns vs. ACTION <0.000 ACUITY-HORIZONS 10.47 0.236 0735 0.724–0.745 vs. ACTION = ns ACTION 5.74 0.677 0.701 0.698–0.712

Figure 1

Conclusions

All three evaluated scores showed very good discriminative capacity for predicting BARC 3 or higher bleeding events in patients undergoing pPCI for AMI.

P5481Predictors of mortality in patients with non-anterior ST-segment elevation myocardial infarction undergoing primary percutaneous coronary intervention

Background

Previous studies have indicated that patients with non-anterior ST-segment elevation myocardial infarction (STEMI) undergoing primary percutaneous coronary intervention (PCI) have a more favorable prognosis compared with anterior STEMI, especially in the short term.

Purpose

Our aim was to identify predictors of increased 30-day mortality in patients with non-anterior STEMI undergoing primary PCI.

Methods

This analysis included 8188 patients referred to primary PCI during 2009–2017, from a prospective electronic registry of a high-volume catheterization laboratory, for whom 30-day follow-up was available. Non-anterior infarction was defined as presence of ST-segment elevation in inferior and/or lateral ECG leads or true posterior MI. Multivariable Cox regression was used to assess the mortality risk at 30 days.

Results

59.4% (n=4863) of the included patients presented with a non-anterior STEMI. Mortality rate was significantly lower in patients with non-anterior vs. anterior STEMI (4.2% vs. 8.3%, p<0.001). Older age (> median of 61, HR 2.2, p=0.002), baseline renal failure (eGFR <60, HR 4.0, p<0.001), Killip class ≥2 (HR 3.8, p<0.001), previous stroke (HR 1.8, p=0.004), non-culprit chronic total occlusion (CTO, HR 2.0, p<0.001) and final TIMI flow grade <3 in the infarct-related artery (HR 3.1, p<0.001) were independently associated with an increased risk of 30-day mortality in non-anterior STEMI. The presence of at least one of these high-risk factors was noted in 61.2% of patients with non-anterior STEMI and was associated with a significantly higher risk of 30-day mortality (HR 18.2, p<0.001), similarly to the overall risk associated with anterior STEMI (HR 22.9, p<0.001), as compared with patients with non-anterior STEMI but without any of the here identified high-risk factors (Figure).

Figure 1

Conclusions

Crude mortality rate was significantly lower in patients with non-anterior vs. anterior STEMI. However, the majority of non-anterior STEMI patients had at least one of the high-risk factors (older age, previous CVI, baseline renal failure, Killip class ≥2, non-culprit CTO or final TIMI flow <3), which predisposed these patients to a similar increase in short-term mortality risk as in patients with anterior STEMI.

P5011Impact of guideline-recommended medical therapy at discharge on long-term mortality in patients with or without left ventricular dysfunction after primary PCI for STEMI

Background

Clinical practice guidelines provide class I recommendation for the use of angiotensin-converting enzyme inhibitors (ACE-I) and beta-blockers in patients with prior myocardial infarction and left ventricular (LV) dysfunction, whereas their use in patients without LV dysfunction is considered to be a class IIa recommendation.

Purpose

Our aim was to comparatively assess the impact of ACE-I and/or beta-blockers on 3-year mortality in patients with or without impaired left ventricular (LV) function undergoing primary percutaneous coronary intervention (PCI) for ST-segment elevation myocardial infarction (STEMI).

Methods

The analysis included 4425 patients admitted for primary PCI during 2009–2015 from a prospective, electronic registry of a high-volume tertiary center, who survived initial hospitalization, and for whom information on LV function and discharge medication were available. Patients were stratified according to LV systolic dysfunction, defined as LVEF <40%. Unadjusted and adjusted Cox regression models were created to investigate the impact of beta-blocker and/or ACE-I therapy on 3-year mortality.

Results

22.9% (n=1013) had LV dysfunction, 23.0% (n=1017) received either an ACE-I or a beta-blocker and 72.2% received both medications at discharge (n=3197). The concurrent use of both ACE-I and beta-blockers was not different in LVEF≥40% vs. LVEF<40% (72.4% vs. 71.7%, p=0.43). The use of at least one of the guideline-recommended medications was associated with a significantly lower 3-year mortality in both patients with LVEF≥40% (18.7% if neither was used, 11.2% if either a beta-blocker or an ACE-I were used and 9.4% if both were used, p=0.001), and LVEF<40% (55.4% if neither was used, 32.5% if either a beta-blocker or an ACE-I were used and 22.9% if both were used, p<0.001) (Figure). After adjusting for significant mortality predictors including older age, diabetes, hypertension, renal failure, previous stroke, Killip class ≥2 and non-culprit chronic total occlusion (CTO), the concurrent use of both a beta-blocker and an ACE-I remained independently associated with lower 3-year mortality in both patients with LVEF<40% (HR 0.30, p<0.001) and LVEF≥40% (HR=0.41, p=0.001). The use of a single agent was independently associated with lower mortality in patients with LVEF<40% (HR 0.45, p=0.002), but not in patients with LVEF≥40% (HR 0.61, p=0.07).

Conclusions

Guideline-recommended use of both a beta-blocker and an ACE-I in post-MI patients was associated with a lower 3-year mortality regardless of the LV function, whereas using only one of the two agents was associated with improved prognosis only in patients with LV dysfunction, but not in patients without LV impairment.

P849Comparison of long-term mortality risk assessed with recalculated (maximal) CADILLAC score vs. baseline (admission) CADILLAC score in STEMI patients undergoing primary PCI

Background

Since patients with STEMI have high rate of adverse events not only during hospital stay, but also during short and long-term follow–up, appropriate risk stratification is a key part of the management of these patients following hospital discharge. CADILLAC score was derived and subsequently validated as accurate clinical tool for identifying patients with heightened risk following index event.

Purpose

We aimed to compare predictive value of recalculated, maximal, (M-) CADILLAC score vs. baseline (B-) CADILLAC score for long-term mortality in hospital survivors.

Methods

From a prospective electronic registry of a high-volume catheterization laboratory in a period from January 2009 to December 2017, a total of 5387 consecutive patients STEMI who underwent primary PCI were included in analysis. For each patient B-CADILLAC score was calculated, and for survivors, we recalculated M-CADILLAC score, incorporating changes in three variable score individual contributors (worsening of Killip class, anemia development and renal function deterioration). As in original score derivation, patients with cardiogenic shock were excluded from analysis. Discrimination of the two risk models was evaluated by the C-statistic, Net reclassification index (NRI) and Integrated Discrimination Improvement (IDI) index.

Results

For 111 (2.1%) patients that died in-hospital, B-CADILLAC very well predicted the event (AUC 0.87, 95% CI 0.86–0.88; p<0.0001) (Figure 1A). For hospital survivors, both evaluated scores showed good discriminative ability for long-term mortality (11.7%) but recalculated M-CADILLAC score was statistically better predictor of long-term mortality, as assessed by C-statistics (Table 1 & Figure 1B):

NRI showed that 38% of patients were reclassified with M-CADILLAC with IDI slope 0.8% higher than in first model.

Table 1 4723 pts (follow-up=90% pts, 41±27 months) AUC 95% CI p B-CADILLAC 0.756 0.744–0.768 p=0.018 M-CADILLAC 0.776 0.754–0.779

Figure 1

Conclusions

Baseline CADILLAC score has very good predictive ability for in-hospital mortality, but recalculated, maximal CADILLAC score offers discriminative advantage in hospital survivors for prediction of long-term mortality in STEMI patients undergoing primary PCI.

P845Comparison of the performance of the five validated risk scores in acute myocardial infarction patients undergoing primary PCI

Background

Several risk scores have been developed to predict mortality of patients with acute myocardial infarction (AMI) undergoing primary percutaneous coronary intervention (pPCI), with limited data on the comparative prognostic value of these models.

Purpose

We aimed to compare the prognostic value of five validated risk scores for in-hospital and one-year mortality of patients with AMI undergoing pPCI.

ume catheterization laboratory in a period from January 2009 to December 2017, a total of 3868 consecutive patients who underwent pPCI were available for analysis. For each patient, the Thrombolysis In Myocardial Infarction (TIMI), Controlled Abciximab and Device Investigation to Lower Late Angioplasty complications (CADILLAC), ACTION Registry-GWTG in-hospital mortality risk score (ACTION), Age, Creatinine, and Ejection Fraction (ACEF), and ZWOLLE risk scores were calculated using required clinical and angiographic characteristics. In-hospital and one-year mortality were assessed (follow-up available for 92% of pts). Calibration and discrimination of the three risk models were evaluated by the Hosmer-Lemeshow (H-L) goodness-of-fit test and C-statistic, respectively.

Results

Mortality rates for in-hospital and one-year mortality were 1.8% and 6.9% respectively. All five scores showed good model calibration as assessed by the H-L test and very good discriminative power for in-hospital and one-year mortality as assessed by C-statistics (Table 1 & Figure 1):

Table 1 Risk score H-L H-L p AUC in-hospital 95% CI Significant p AUC one-year 95% CI Significant p ZWOLLE 1.3 0.7 0.90 0.89–0.91 vs. CADILLAC <0.05 0.75 0.74–0.77 vs. TIMI <0.005 ACTION 13.1 0.1 0.87 0.86–0.88 vs. TIMI <0.005 0.79 0.77–0.80 CADILLAC 5.5 0.2 0.85 0.84–0.86 vs. TIMI <0.01 0.81 0.80–0.83 vs. ZWOLLE <0.000 vs. TIMI <0.000 ACEF 9.9 0.3 0.814 0.83–0.85 0.80 0.78–0.81 vs. ZWOLLE <0.000 vs. TIMI <0.05 TIMI 7.1 0.3 0.79 0.78–0.80 0.76 0.75–0.78

Figure 1

Conclusion

Risk stratification of patients with AMI undergoing pPCI using the ZWOLLE, ACTION, CADILLAC, ACEF or TIMI risk scores enables accurate identification of high-risk patients for in-hospital and one-year mortality in an all-comers population. Among evaluated scores, ZWOLLE model was better fitted for prediction of in-hospital mortality while CADILLAC and ACEF better predicted late events.

Medication Overuse Headache: Clinical Features Predicting Treatment Outcome at 1-Year Follow-Up

We present a prospective study of 240 patients with medication overuse headache (MOH) treated with drug withdrawal and prophylactic medications. At 1-year follow-up, 137 (57.1%) patients were without chronic headache and without medication overuse, eight (3.3%) patients did not improve after withdrawal and 95 (39.6%) relapsed developing recurrent overuse. Age at time of MOH diagnosis, regular use of benzodiazepines, frequency and Migraine Disability Assessment (MIDAS) score of chronic headache, age at onset of primary headache, frequency and MIDAS score of primary headache, ergotamine compound overuse and daily drug intake were significantly different between successfully and unsuccessfully treated patients. Multivariate analysis determined the frequency of primary headache disorder, ergotamine overuse and disability of chronic headache estimated by MIDAS as independent predictors of treatment efficacy at 1-year follow-up.

Ureteral Metastasis Secondary to Prostate Cancer: A Case Report

Prostate cancer is very frequent, but secondary ureteral metastasis are extremely rare. We present a 55 year old man with a 2 month history of right flank pain and lower urinary tract symptoms. Prostatic specific antigen of 11.3 ng/mL. Computed tomography showed right hydroureteronephrosis, a developing urinoma and right iliac adenopathies. He underwent right ureteronephrectomy, iliac lymphadenectomy and prostate biopsy. Pathology revealed prostatic carcinoma infiltrating the ureteral muscularis propria, without mucosal involvement. There are 46 reported cases of prostate cancer with ureteral metastases. Ureteral metastasis are a rare cause of renal colic and need of a high index of suspicion.

Relationship of thoracic kyphosis and lumbar lordosis to bone mineral density in women

The relationship between spinal curvature and bone mineral density (BMD) in women was examined. Significant relationships were observed between spinal curvature and BMD in both pre- and postmenopausal women. Excessive spinal curvature may be associated with low bone mass in premenopausal women.

INTRODUCTION

The purpose of this study was to examine the associations between spinal measurements of thoracic and lumbar curvatures and bone mineral density in pre- and postmenopausal women.

METHODS

The data for this study were obtained from the Texas Woman's University Pioneer Project. Female participants (n = 242; premenopausal n = 104, postmenopausal n = 138) between the ages of 18 and 60 years were evaluated on multiple health measures. Thoracic and lumbar curvatures were measured with a 24-in. (60 cm) flexicurve. Bone mineral density was assessed via dual-energy X-ray absorptiometry (Lunar DPX IQ, version 4.6e). Pearson correlations and logistic regression analysis were used to examine the associations between the obtained spinal curvature measurements and bone mineral density. Significance was set at p < .05.

RESULTS

Significant correlations were observed for the femoral neck and lumbar spine bone mineral density with thoracic and lumbar curve in premenopausal women (r = -.344 to - .525; p < .001). Slightly weaker, but significant, correlations were observed for femoral neck and lumbar spine in relation to thoracic and lumbar curve in postmenopausal women (r = -.288 to -.397; p < .01). Premenopausal women with thoracic curvature greater than 4 cm had a greater risk of having low bone mass compared to premenopausal women with less than 4 cm of curvature (odds ratio = 3.982, 95 % CI = 1.206, 13.144).

CONCLUSIONS

The observed negative relationship suggests that as either thoracic or lumbar curvature increases, the regional bone mineral density decreases in both pre- and postmenopausal women.

On the mechanism underlying photosynthetic limitation upon trigger hair irritation in the carnivorous plant Venus flytrap (Dionaea muscipula Ellis)

Mechanical stimulation of trigger hairs on the adaxial surface of the trap of Dionaea muscipula leads to the generation of action potentials and to rapid leaf movement. After rapid closure secures the prey, the struggle against the trigger hairs results in generation of further action potentials which inhibit photosynthesis. A detailed analysis of chlorophyll a fluorescence kinetics and gas exchange measurements in response to generation of action potentials in irritated D. muscipula traps was used to determine the 'site effect' of the electrical signal-induced inhibition of photosynthesis. Irritation of trigger hairs and subsequent generation of action potentials resulted in a decrease in the effective photochemical quantum yield of photosystem II (Φ(PSII)) and the rate of net photosynthesis (A(N)). During the first seconds of irritation, increased excitation pressure in photosystem II (PSII) was the major contributor to the decreased Φ(PSII). Within ∼1 min, non-photochemical quenching (NPQ) released the excitation pressure at PSII. Measurements of the fast chlorophyll a fluorescence transient (O-J-I-P) revealed a direct impact of action potentials on the charge separation-recombination reactions in PSII, although the effect seems to be small rather than substantial. All the data presented here indicate that the main primary target of the electrical signal-induced inhibition of photosynthesis is the dark reaction, whereas the inhibition of electron transport is only a consequence of reduced carboxylation efficiency. In addition, the study also provides valuable data confirming the hypothesis that chlorophyll a fluorescence is under electrochemical control.

Gabaculine alters plastid development and differentially affects abundance of plastid-encoded DPOR and nuclear-encoded GluTR and FLU-like proteins in spruce cotyledons

Synthesis of 5-aminolevulinic acid (ALA) represents a rate limiting step in the tetrapyrrole biosynthetic pathway, and is regulated by metabolic feedback control of glutamyl-tRNA reductase (GluTR) activity. The FLU protein has been attributed to this regulation. Later in the biosynthetic pathway, reduction of protochlorophyllide (Pchlide), catalyzed by protochlorophyllide oxidoreductase (POR), ensures another important regulatory step in the chlorophyll biosynthesis. In the present work, we investigated the expression and cellular abundance of nuclear-encoded and plastid-encoded proteins involved in ALA synthesis and Pchlide reduction in Norway spruce (Picea abies L. Karst.) as a representative of plant species with high ability to synthesize chlorophyll in the dark. Using dark-grown, light/dark-grown and gabaculine-treated seedlings, we demonstrated that gabaculine-impaired etiochloroplast and chloroplast development has no negative effect on GluTR accumulation in the cotyledons. However, in contrast to control plants, the relative amount of GluTR was similar both in the dark-grown and light/dark-grown gabaculine-treated seedlings. We identified a partial sequence of the FLU-like gene in Norway spruce, and using antibodies against the FLU-like protein (FLP), we showed that FLP accumulated mostly in the dark-grown control seedlings and gabaculine-treated seedlings. In contrast to nuclear-encoded GluTR and FLP, accumulation of plastid-encoded light-independent POR (DPOR) was sensitive to gabaculine treatment. The levels of DPOR subunits were substantially lower in the light/dark-grown control seedlings and gabaculine-treated seedlings, although the corresponding genes chlL, chlN and chlB were expressed. Since we analyzed the samples with different plastid types, plastid ultrastructure and physiological parameters like Pchlide and chlorophyll contents, in vivo chlorophyll fluorescence and photosynthetic efficiency of the seedlings were characterized. Apart from etiochloroplast-specific accumulation of the DPOR subunits, we described, in some detail, additional specific features of chlorophyll biosynthesis in the spruce seedlings that differ from those known in angiosperms.

Trap closure and prey retention in Venus flytrap (Dionaea muscipula) temporarily reduces photosynthesis and stimulates respiration

BACKGROUND AND AIMS

The carnivorous plant Venus flytrap (Dionaea muscipula) produces a rosette of leaves: each leaf is divided into a lower part called the lamina and an upper part, the trap, with sensory trigger hairs on the adaxial surface. The trap catches prey by very rapid closure, within a fraction of a second of the trigger hairs being touched twice. Generation of action potentials plays an important role in closure. Because electrical signals are involved in reduction of the photosynthetic rate in different plant species, we hypothesized that trap closure and subsequent movement of prey in the trap will result in transient downregulation of photosynthesis, thus representing the energetic costs of carnivory associated with an active trapping mechanism, which has not been previously described.

METHODS

Traps were enclosed in a gas exchange cuvette and the trigger hairs irritated with thin wire, thus simulating insect capture and retention. Respiration rate was measured in darkness (RD). In the light, net photosynthetic rate (AN), stomatal conductance (gs) and intercellular CO2 concentration (ci) were measured, combined with chlorophyll fluorescence imaging. Responses were monitored in the lamina and trap separately.

KEY RESULTS

Irritation of trigger hairs resulted in decreased AN and increased RD, not only immediately after trap closure but also during the subsequent period when prey retention was simulated in the closed trap. Stomatal conductance remained stable, indicating no stomatal limitation of AN, so ci increased. At the same time, the effective quantum yield of photosystem II (PSII) decreased transiently. The response was confined mainly to the digestive zone of the trap and was not observed in the lamina. Stopping mechanical irritation resulted in recovery of AN, RD and PSII.

CONCLUSIONS

We put forward the first experimental evidence for energetic demands and carbon costs during insect trapping and retention in carnivorous plants, providing a new insight into the cost/benefit model of carnivory.

A novel insight into the regulation of light-independent chlorophyll biosynthesis in Larix decidua and Picea abies seedlings

Light-independent chlorophyll (Chl) biosynthesis is a prerequisite for the assembly of photosynthetic pigment-protein complexes in the dark. Dark-grown Larix decidua Mill. seedlings synthesize Chl only in the early developmental stages and their Chl level rapidly declines during the subsequent development. Our analysis of the key regulatory steps in Chl biosynthesis revealed that etiolation of initially green dark-grown larch cotyledons is connected with decreasing content of glutamyl-tRNA reductase and reduced 5-aminolevulinic acid synthesizing capacity. The level of the Chl precursor protochlorophyllide also declined in the developing larch cotyledons. Although the genes chlL, chlN and chlB encoding subunits of the light-independent protochlorophyllide oxidoreductase were constitutively expressed in the larch seedlings, the accumulation of the ChlB subunit was developmentally regulated and ChlB content decreased in the fully developed cotyledons. The efficiency of chlB RNA-editing was also reduced in the mature dark-grown larch seedlings. In contrast to larch, dark-grown seedlings of Picea abies (L.) Karst. accumulate Chl throughout their whole development and show a different control of ChlB expression. Analysis of the plastid ultrastructure, photosynthetic proteins by Western blotting and photosynthetic parameters by gas exchange and Chl fluorescence measurements provide additional experimental proofs for differences between dark and light Chl biosynthesis in spruce and larch seedlings.