Etiologies and predictors of mortality in an all-comer population of patients with non-ischemic heart failure

BACKGROUND

Despite progress in diagnosis and therapy of heart failure (HF), etiology and risk stratification remain elusive in many patients.

METHODS

The My Biopsy HF Study (German clinical trials register number: DRKS22178) is a retrospective monocentric study investigating an all-comer population of patients with unexplained HF based on a thorough workup including endomyocardial biopsy (EMB).

RESULTS

655 patients (70.9% men, median age 55 [45/66] years) with non-ischemic, non-valvular HF were included in the analyses. 489 patients were diagnosed with HF with reduced ejection fraction (HFrEF), 52 patients with HF with mildly reduced ejection fraction (HFmrEF) and 114 patients with HF with preserved ejection fraction (HFpEF). After a median follow-up of 4.6 (2.5/6.6) years, 94 deaths were enumerated (HFrEF: 68; HFmrEF: 8; HFpEF: 18), equating to mortality rates of 3.3% and 11.6% for patients with HFrEF, 7.7% and 15.4% for patients with HFmrEF and 5.3% and 11.4% for patients with HFpEF after 1 and 5 years, respectively. In EMB, we detected a variety of putative etiologies of HF, including incidental cardiac amyloidosis (CA, 5.8%). In multivariate logistic regression analysis adjusting for age, sex and comorbidities only CA, age and NYHA functional class III + IV remained independently associated with all-cause mortality (CA: HRperui 3.13, 95% CI 1.5-6.51; p = 0.002).

CONCLUSIONS

In an all-comer population of patients presenting with HF of unknown etiology, incidental finding of CA stands out to be independently associated with all-cause mortality. Our findings suggest that prospective trials would be helpful to test the added value of a systematic and holistic work-up of HF of unknown etiology.

Coronary intravascular lithotripsy and rotational atherectomy for severely calcified stenosis: Results from the ROTA.shock trial

BACKGROUND

Severely calcified coronary lesions present a particular challenge for percutaneous coronary intervention.

AIMS

The aim of this randomized study was to determine whether coronary intravascular lithotripsy (IVL) is non-inferior to rotational atherectomy (RA) regarding minimal stent area (MSA).

METHODS

The randomized, prospective non-inferiority ROTA.shock trial enrolled 70 patients between July 2019 and November 2021. Patients were randomly (1:1) assigned to undergo either IVL or RA before percutaneous coronary intervention of severely calcified coronary lesions. Optical coherence tomography was performed at the end of the procedure for primary endpoint analysis.

RESULTS

The primary endpoint MSA was lower but non-inferior after IVL (mean: 6.10 mm2 , 95% confidence interval [95% CI]: 5.32-6.87 mm2 ) versus RA (6.60 mm2 , 95% CI: 5.66-7.54 mm2 ; difference in MSA: -0.50 mm2 , 95% CI: -1.52-0.52 mm2 ; non-inferiority margin: -1.60 mm2 ). Stent expansion was similar (RA: 0.83 ± 0.10 vs. IVL: 0.82 ± 0.11; p = 0.79). There were no significant differences regarding contrast media consumption (RA: 183.1 ± 68.8 vs. IVL: 163.3 ± 55.0 mL; p = 0.47), radiation dose (RA: 7269 ± 11288 vs. IVL: 5010 ± 4140 cGy cm2 ; p = 0.68), and procedure time (RA: 79.5 ± 34.5 vs. IVL: 66.0 ± 19.4 min; p = 0.18).

CONCLUSION

IVL is non-inferior regarding MSA and results in a similar stent expansion in a random comparison with RA. Procedure time, contrast volume, and dose-area product do not differ significantly.

COVID-19 infection and its impact on case-fatality in patients with pulmonary embolism

Background

Although a high prevalence of pulmonary embolism (PE) has been reported as a complication during severe COVID-19 infections in critical ill patients, nationwide data of hospitalized patients with COVID-19 with PE is still limited. Thus, we sought to analyze seasonal trends and predictors of in-hospital case-fatality in patients with COVID-19 and PE in Germany.

Methods

We used the German nationwide inpatient sample to analyze all data on hospitalizations for COVID-19 patients with and without PE in Germany during the year 2020 and to compare changes of PE prevalence to 2019.

Results

We analyzed data of 176,137 hospitalizations because of COVID-19 in 2020. Among those, PE was recorded in 1.9% (n=3,362) of discharge or death certificates. Almost one third of patients with COVID-19 and PE died during the in-hospital course (28.7%). The case-fatality rate increased with patients' age peaking in the 9th life-decade. Regardless of COVID-19, 196,203 inpatients were diagnosed with PE in Germany between 2019 and 2020. The number of PE hospitalizations were widely equally distributed between both years (98,485 vs. 97,718), while the case-fatality rate of all patients with PE was slightly lower in 2019 compared to 2020 (12.7% vs. 13.1%, P<0.001). In contrast, considerable differences in prevalence and case-fatality were demonstrated in 2020 regarding PE patients with and without COVID-19 infection (28.7% vs. 13.1%, P<0.001) (Figure 1). A COVID-19-infection was associated with a 2.8-fold increased risk of case-fatality in patients with PE (OR 2.81, 95% CI 1.66–2.12, P<0.001).

Conclusions

In Germany, the prevalence of PE events complicating hospitalizations was similar in 2019 and 2020. However, the fatality rate among patients with COVID-19-associated PE was substantially higher than that in those without either COVID-19 or PE, indicating an additive prognostic effect of these two conditions.

Funding Acknowledgement

Type of funding sources: None.

Psoriasis and its impact on the clinical outcome of patients with pulmonary embolism

Background

Venous thromboembolism (VTE) is common and associated with high morbidity and mortality. Although chronic inflammation was not categorized as a traditional risk factor for VTE, chronic inflammation might increase the risk to develop VTE events.

While studies confirmed an increased cardiovascular morbidity and mortality in psoriatic patients, data regarding the influence of psoriasis on patients' cardiovascular profile and on prognosis of patients with pulmonary embolism (PE) are sparse.

Purpose

We aimed to investigate the impact of psoriasis on prognosis of PE patients.

Methods

Hospitalized PE patients were stratified for psoriasis and the impact of psoriasis on outcome was investigated in the German nationwide inpatient sample of the years 2005–2017 (source: Research Data Center (RDC) of the Federal Statistical Office and the Statistical Offices of the federal states, DRG Statistics 2005–2017, own calculations).

Results

Overall, 1,076,384 hospitalizations of PE patients (53.7% females, median age 72.0 [60.0–80.0] years) were recorded in Germany 2005–2017. Among these, 3,145 patients were additionally coded with psoriasis (0.3%). Psoriatic PE patients were younger (68.0 [57.0–76.0] vs. 72.0 [60.0–80.0] years, P&lt;0.001) and more often male (64.1% vs. 46.3%, P&lt;0.001). The prevalence of VTE risk factors, traditional cardiovascular risk factors and cardiovascular comorbidities was higher in psoriatic than in non-psoriatic individuals: All investigated traditional cardiovascular risk factors such as essential arterial hypertension (49.8% vs. 43.1%, P&lt;0.001), diabetes mellitus (24.4% vs. 18.7%, P&lt;0.001), hyperlipidaemia (14.1% vs. 12.0%, P&lt;0.001), as well as obesity (19.6% vs. 9.6%, P&lt;0.001) and atherosclerotic comorbidities like coronary artery disease (15.2% vs. 13.8%, P=0.022) and peripheral artery disease (3.6% vs. 2.9%, P=0.010) were more prevalent in PE patients with psoriasis.

Psoriatic PE patients showed a lower in-hospital case-fatality rate (11.1% vs. 16.0%, P&lt;0.001), confirmed by logistic regressions showing an independent association of psoriasis with reduced case-fatality rate (OR 0.73 [95% CI 0.65–0.82], P&lt;0.001), despite higher prevalence of pneumonia (24.8% vs. 23.2%, P=0.029). Psoriasis was an independent predictor for gastro-intestinal bleeding (OR 1.35 [95% CI 1.04–1.75], P=0.023) and transfusion of blood constituents (OR 1.23 [95% CI 1.11–1.36], P&lt;0.001).

Conclusions

Overall, only a minority (0.3%) of all PE cases were coded additionally with psoriasis. PE patients with psoriasis were hospitalized in median four years earlier than those without. Although psoriasis was associated with an unfavorable cardiovascular-risk and VTE-risk profile in PE patients, our data demonstrate a lower in-hospital mortality rate in psoriatic PE, which might be mainly driven by younger age. Our findings may improve the clinical management of these patients and contribute evidence for relevant systemic manifestation of psoriasis.

Funding Acknowledgement

Type of funding sources: None.

Patterns of pulmonary function and mortality in chronic heart failure, results from the MyoVasc study

Background

Preclinical evidence suggests that pulmonary fibrosis due to left heart disease may represent end-organ damage in heart failure (HF). Vice versa, decreased pulmonary function is related to worsening of heart failure in the absence of obstructive airway pattern.

Purpose

This study investigated the relationship between patterns of pulmonary function (i.e. obstruction and restriction) and mortality in chronic HF.

Methods

For the present analysis data from the MyoVasc-study (N=3,289) were analysed. During a five-hour examination in the dedicated study center, systematic phenotyping was performed in a highly standardized setting. Chronic HF was defined as American Heart Association HF Stage C/D. Information on pulmonary function was assessed via body plethysmography (MasterScreen Body, Carefusion, Germany). Participants with forced expiratory ratio &lt;0.7 or COPD were categorized as obstructive, while restriction was defined as reduction in total lung capacity. Information on vital status was obtained via registration offices.

Results

The analysis sample comprised 1,509 individuals with chronic heart failure and information on pulmonary function, of whom 286 had HF with reduced ejection fraction (HFrEF), 559 HF with preserved ejection fraction (HFpEF), and 333 HFpEFborderline. The mean age was 64.6±11.3 years, 38.7% were female. In the sample 124 subjects had pulmonary restriction and 400 individuals had an obstruction. During a median time to follow up of 3.70 (inter quartile range 1.25 to 4.00) years, death occurred in 170 individuals. Among clusters of pulmonary function most participants died in the restriction group (25.0%), followed by pulmonary obstruction (12.2%) and normal pulmonary function (7.3%, P for trend &lt;0.001). Cox- regression analysis adjusted for age, sex and height revealed pulmonary restriction (hazard ratio (HR) 3.00 [95% confidence interval 2.04–4.42], P&lt;0.001] and obstruction (HR 1.61 [1.11–2.35], P=0.01) as predictors of all-cause death. After additional controlling for traditional cardiovascular risk factors and the clinical profile only pulmonary restriction remained an independent predictor of mortality (HRrestriction 2.12 [1.50–3.43]; P=0.002; HRobstruction 1.35 [0.91–2.00]; P=0.10). Among HF phenotypes obstruction was only in individuals with HFpEF an independent predictor of all-cause death (HRHFpEF 2.60 [1.29–5.23]; P=0.007; HRHFpEFborderline 1.58 [0.70–3.57]; P=0.27; HRHFrEF 0.96 [0.52–1.78]; P=0.90), while pulmonary restriction was found to be predictive for death only in subjects with HFpEFborderline (HRHFpEF 2.15 [0.70–6.64]; P=0.18; HRHFpEFborderline: HR 5.47 [2.56–11.68]; P&lt;0.001; HRHFrEF 1.74 [0.88–3.46]; P=0.11)

Conclusion

In chronic heart failure, pulmonary restriction was a stronger predictor of mortality than obstructive airway pattern. The present analysis supports the hypothesis of pulmonary fibrosis as end-organ damage in HF, and may potentially represent a therapeutic target.

Funding Acknowledgement

Type of funding sources: Public Institution(s). Main funding source(s): German Center for Cardiovascular Research (DZHK)

Prevalence and outcome of cardiac amyloidosis in an all-comer population of patients with non-ischaemic heart failure

Background

Cardiac amyloidosis (CA) is increasingly recognized as an underlying cause of heart failure with preserved ejection fraction (HFpEF), associated with high morbidity and mortality. However, most studies, solely investigated the prevalence of CA in special subgroups including HFpEF and severe aortic valve disease.

Purpose

With the present study we sought to investigate prevalence of different phenotypes of CA in an all comer-population of patients with non-ischaemic heart failure (HF) and to analyze the impact of CA on all-cause mortality.

Methods

The My Biopsy HF-Study (German clinical trials register number: 22178) is a retrospective monocentric study investigating the underlying etiology of HF in an all-comer population of patients with HF of unknown etiology. Patients presenting with symptoms of HF at the University Medical Centre between 14/10/2012 and 01/03/2021, who underwent endomyocardial biopsy (EMB) were enrolled in the present study. Ischaemic HF and valvular HF were ruled out prior to EMB. Specimens were sent for further examination to a specialized laboratory approved by the Food and Drug Administration

Results

Between October 2012 and March 2021, 767 patients (71.6% men) with HF of unknown etiology were included. Mean age at the time of presentation was 55.4 years (±14.4). Altogether, 72.5% of the patients presented with HF with reduced ejection fraction (HFrEF), 7.1% were diagnosed with HF with mid-range ejection fraction (HFmrEF) and 20.4% with HFpEF. Based on histological examination and genotyping, CA was diagnosed in 44 (5.7%) patients (immunglobulin light chain [AL] CA: 15 patients; variant transthyretin [ATTRv] CA: 6 patients; wild type transthyretin [ATTRwt] CA: 21 patients; de novo CA: 2 patients). Patients with CA were older compared with patients without CA (69.4±11.4 vs. 54.1±14.5; p&lt;0.0001), had a higher prevalence of arterial hypertension (68.2% vs. 50.9%; p=0.045) and showed a better left ventricular ejection fraction based on echocardiographic examination (47.5% vs. 32.6%; p&lt;0.0001). With respect to biomarker expression, levels of both brain natriuretic peptide and high-sensitive troponin I were significantly higher in patients without CA (BNP: 914.1 vs 612; p=0.01; troponin I: 812.8 vs. 171.7; p=0.006). In univariate logistic regression analysis CA was associated with a significant all-cause mortality (hazard ratio [HR] per unit increase [ui], 5.17, 95% CI, 2.93–9.08; p&lt;0.0001), even after adjustment for classical cardiovascular risk factors (HRperui 3.12, 95% CI, 1.11–8.76; p=0.03) and comorbidities like chronic obstructive pulmonary disease, chronic kidney disease and stroke (HRperui 2.93, 95% CI, 1.2–7.15; p=0.018).

Conclusions

Among patients presenting with HF of unknown etiology, including patients with HFpEF, HFmrEF and HFrEF, cardiac amyloidosis is the underlying cause of HF in 5.7% of patients and is independently associated with all-cause mortality.

Funding Acknowledgement

Type of funding sources: None.

Impact of cardiac amyloidosis on outcomes of patients hospitalized with heart failure in Germany

Background

Amyloidosis is a multi-systemic disease resulting from deposition of misfolded proteins as insoluble fibrils in the interstitium of affected organs including the heart, subsequently leading to organ failure. Cardiac involvement is predominantly observed in light chain (AL) amyloidosis and wild-type transthyretin (ATTRwt) amyloidosis.

Purpose

We aimed to investigate prevalence and prognostic implications of cardiac amyloidosis of any etiology on outcomes of hospitalized patients with heart failure (HF) in Germany.

Methods

We analyzed data of the German nationwide inpatient sample (2005–2018) of patients hospitalized for HF (including myocarditis with HF and heart transplantation with HF). HF patients with amyloidosis (defined as cardiac amyloidosis [CA]) were compared with those HF patients without amyloidosis and impact of CA on outcomes was assessed (source: Research Data Center (RDC) of the Federal Statistical Office and the Statistical Offices of the federal states, DRG Statistics 2005–2018, and own calculations).

Results

During this fourteen-year observational period 5,478,835 hospitalizations of HF patients were analyzed. Amyloidosis was coded in 5,407 hospitalizations of HF patients (0.1%). Prevalence of CA was 1.87 hospitalizations per 100,000 German population. CA patients were younger (75.0 [IQR 67.0/80.0] vs. 79.0 [72.0–85.0] years, p&lt;0.001), predominantly male (68.9%) and had a higher prevalence of cancer (14.8% vs. 3.6%, P&lt;0.001) compared with HF without amyloidosis. Although patients without amyloidosis had a pronounced cardiovascular risk profile -especially arterial hypertension (45.4% vs. 35.6%; p&lt;0.001) and diabetes mellitus (38.9% vs. 18.5%; p&lt;0.001)- and a higher prevalence of concomitant coronary artery disease (40.5% vs. 34.5%; p&lt;0.001) and chronic obstructive pulmonary disease (17.1% vs. 9.4%; p&lt;0.001), adverse in-hospital events including necessity of transfusions of blood constituents (7.1% vs. 5.4%, p&lt;0.001) and cardio-pulmonary resuscitation (CPR, 2.7% vs. 1.4%; p&lt;0.001) were more frequent in CA. CA was independently associated with acute kidney failure (OR 1.40 [95% CI 1.28–1.52], p&lt;0.001), CPR (OR 1.58 [95% CI 1.34–1.86], p&lt;0.001), intracerebral bleeding (OR 3.13 [95% CI 1.68–5.83], p&lt;0.001) and in-hospital mortality in the 6th and 8th decade of life (6thdecade: OR 1.40 [95% CI 1.01–1.94], p=0.042; 8thdecade: OR 1.18 [95% CI 1.03–1.35], p=0.02).

Conclusions

CA was identified as an independent risk factor for complications and in-hospital mortality in HF patients. Physicians should be aware of this issue concerning treatments and monitoring of CA-patients.

Funding Acknowledgement

Type of funding sources: None.

Coronary venous therapy to improve microvascular dysfunction

The coronary circulation is a complex system in which vascular resistances are determined by an interplay of forces in at least three compartments: the epicardial, the microvascular, and the venous district. Cardiologists, and particularly interventional cardiologists, normallly place the focus of their attention on diseases of the epicardial coronary circulation as possible causes of coronary syndromes and neglect the importance of the other two compartments of coronary circulation. The study of the coronary microcirculation, an increasingly recognized source of ischemia, has long been disregarded, but is witnessing a revival since the (re-)introduction of diagnostic tools in the better equipped catheterization laboratories. Unfortunately, to date our understanding of coronary microvascular disease remains incomplete and the numerous proposed classifications fail to reflect its complexity. Further, no specific therapy for these disorders is available. The coronary venous circulation is an even more neglected third vascular district. Its role in regulating coronary resistances is almost completely unexplored, but inital evidence suggests that the modulation of venous pressure might help improve coronary perfusion. Coronary sinus interventions are a group of invasive techniques (both surgical and catheter-based) that are designed to treat ischaemic heart disease by increasing coronary venous pressure and therefore redistributing coronary blood flow towards the endocardium. In this review paper, we revise the role of these interventions with particular focus on acute and chronic coronary microvascular disease.

Temporal trends, sex-differences and outcomes of patients hospitalized for heart failure in Germany

Background

Despite remarkable improvements in treatment of cardiovascular disease, heart failure (HF) is still characterized by a high mortality rate. Sex-specific differences in HF have been described, but underlying reasons are widely unexplored. Thus, we aimed to investigate sex differences of patients hospitalized for HF in a nationwide cohort.

Methods

The nationwide German inpatient sample (2005–2016) was used for this sex-specific analyses. Temporal trends on hospitalizations, mortality, and treatments were analyzed and independent predictors of adverse outcomes identified.

Results

The present analysis comprises 4,538,977 hospitalizations due to HF (52.0%women) in Germany (2005–2016). Although women were older (median 82 (IQR75–87) vs. 76 (69–82), P&lt;0.001), coronary artery disease (CAD, 50.3% vs. 30.7%, P&lt;0.001) was more prevalent in men, who were more often treated with PCI (3.4% vs. 1.4%, P&lt;0.001) and implantable cardioverter-defibrillator (2.2% vs. 0.5%, P&lt;0.001). In-hospital mortality was significantly lower in men than in women (8.9% vs. 10.2, P=0.001) and was reduced in patients who received PCI or implantation of an ICD.

While total numbers of hospitalizations between 2005 and 2016 increased in both men (β-estimate 7185.71 (95% CI 6502.23 to 7869.18), P&lt;0.001) and women (β-estimate 5297.60 (95% CI 4557.37 to 6037.83), P&lt;0.001) as well as almost all comorbid co-conditions, in-hospital mortality rate decreased more distinctly in women (β-estimate −0.41 (95% CI: −0.42 to −0.39), P&lt;0.001) compared to men (β-estimate −0.29 (95% CI: −0.30 to −0.27), P&lt;0.001).

Conclusions

Interventional treatments of HF were associated with improved outcomes and equally beneficial for both sexes. However, they were more often used in male HF patients, in which CAD is significantly more frequent than in female HF patients. This may explain the higher case fatality rate of HF in females.

Funding Acknowledgement

Type of funding source: Public grant(s) – National budget only. Main funding source(s): German Federal Ministry of Education and Research (BMBF)

Global longitudinal strain predicts outcome in chronic heart failure across American Heart Association stages: results from the MyoVasc study

Background

Global longitudinal strain (GLS) demonstrated a superior prognostic value over left ventricular ejection fraction (LVEF) in acute heart failure (HF). Its prognostic value across American Heart Association (AHA) stages of HF – especially under considering of conventional echocardiographic measures of systolic and diastolic function – has not yet been comprehensively evaluated.

Purpose

To evaluate the prognostic value of GLS for HF-specific outcome across AHA HF stages A to D.

Methods

Data from the MyoVasc-Study (n=3,289) were analysed. Comprehensive clinical phenotyping was performed during a five-hour investigation in a dedicated study centre. GLS was measured offline utilizing QLab 9.0.1 (PHILIPS, Germany) in participants presenting with sinus rhythm during echocardiography. Worsening of HF (comprising transition from asymptomatic to symptomatic HF, HF hospitalization, and cardiac death) was assessed during a structured follow-up with subsequent validation and adjudication of endpoints. AHA stages were defined according to current guidelines.

Results

Complete information on GLS was available in 2,400 participants of whom 2,186 categorized to AHA stage A to D were available for analysis. Overall, 434 individuals were classified as AHA stage A, 629 as stage B and 1,123 as stage C/D. Mean GLS increased across AHA stages of HF: it was lowest in stage A (−19.44±3.15%), −18.01±3.46% in stage B and highest in AHA stage C/D (−15.52±4.64%, P for trend &lt;0.0001). During a follow-up period of 3.0 [1.3/4.0] years, GLS denoted an increased risk for worsening of HF after adjustment for age and sex (hazard ratio, HRGLS [per standard deviation (SD)] 1.97 [95% confidence interval 1.73/2.23], P&lt;0.0001) in multivariable Cox regression analysis. After additional adjustment for cardiovascular risk factors, clinical profile, LVEF and E/E' ratio, GLS was the strongest echocardiographic predictor of worsening of HF (HRGLS [per SD] 1.47 [1.20/1.80], P=0.0002) in comparison to LVEF (HRLVEF [per SD] 1.23 [1.02/1.48], P=0.031) and E/E' ratio (HRE/E' [per SD] 1.12 [0.99/1.26], P=0.083). Interestingly, when stratifying for AHA stages, GLS denoted a similar increased risk for worsening of HF in individuals classified as AHA stage A/B (HRGLS [per SD] 1.63 [1.02/2.61], P=0.039) and in those classified as AHA stage C/D (HRGLS [per SD] 1.95 [1.65/2.29], P&lt;0.0001) after adjustment for age and sex. For further evaluation, Cox regression models with interaction analysis indicated no significant interaction for (i) AHA stage A/B vs C/D (P=0.83) and (ii) NYHA functional class &lt;II vs ≥II in individuals classified as AHA stage C/D (P=0.12).

Conclusions

GLS demonstrated a higher predictive value for worsening of HF than conventional echocardiographic measures of systolic and diastolic function. Interestingly, GLS indicated an increased risk for worsening of HF across AHA stages highlighting its potential value to advance risk prediction in chronic HF.

Funding Acknowledgement

Type of funding source: Public grant(s) – National budget only. Main funding source(s): German Center for Cardiovascular Research (DZHK), Center for Translational Vascular Biology (CTVB) of the University Medical Center of the Johannes Gutenberg-University Mainz

In-hospital outcomes of catheter-directed thrombolysis in patients with pulmonary embolism

Background and purpose

Catheter-directed treatment of acute pulmonary embolism (PE) is technically advancing. Recent guidelines acknowledge this treatment option for patients with overt or imminent haemodynamic decompensation, particularly when systemic thrombolysis is contraindicated or has failed. We investigated baseline characteristics and in-hospital outcomes of patients with PE who underwent catheter-directed thrombolysis (CDT) in the German nationwide inpatient cohort.

Methods

Data from hospitalizations with PE between 2005 and 2016 were collected by the Federal Office of Statistics (Statistisches Bundesamt) in Germany and included in this analysis. Patients with PE who underwent CDT were compared with patients receiving systemic thrombolysis, and those without thromboytic or other reperfusion treatment.

Results

We analyzed data from 978,094 hospitalized patients with PE. Of these, 41,903 (4.3%) patients received thrombolytic treatment (systemic thrombolysis in 4.2%, CDT in 0.1%). Among PE patients with shock, CDT was associated with lower in-hospital mortality compared to systemic thrombolysis (OR, 0.29, 95% CI 0.13–0.66, P=0.003). No intracranial bleeding occurred among PE patients with shock who received CDT. Among haemodynamically stable PE patients with right ventricular (RV) dysfunction (intermediate-risk PE), CDT also was associated with a lower risk of in-hospital mortality compared to systemic thrombolysis (OR, 0.52 [95% CI 0.38–0.70]; P&lt;0.001) or no thrombolytic treatment (0.45 [95% CI 0.33–0.62]; P&lt;0.001).

Conclusion

In the German nationwide inpatient cohort, CDT was associated with lower in-hospital mortality rates compared to systemic thrombolysis. Prospective controlled data are urgently needed to determine the true value of this treatment option in acute PE.

Funding Acknowledgement

Type of funding source: Public grant(s) – National budget only. Main funding source(s): This study was supported by the German Federal Ministry of Education and Research (BMBF 01EO1503).

Tissue factor cytoplasmic tail regulates myeloid cell derived superoxide formation and TGF-beta 1 driven cardiac remodeling in myocardial infarction

Background

In the setting of myocardial infarction (MI), patients with coronary no-reflow and/or delayed presentation after onset of symptoms (sub-acute MI) are inflicted by severe thrombo-inflammation and are marked by worse clinical outcome. However, it is unclear whether tissue factor (TF) contributes to outcome post MI solely by the regulatory functions of its cytoplasmic tail independently of its coagulation activity.

Purpose

We analyzed the role of the TF cytoplasmic domain in the recruitment of myeloid cells into the infarcted myocardium and the consequences on cardiac remodeling, scar formation, development of heart failure and survival post MI.

Methods

Twelve Patients enrolled in the MICAT (Mainzer Intracoronary Database, ClinicalTrials.gov Identifier: NCT02180178) study were examined. Patients with sub-acute MI and stable coronary artery disease were defined and monocytes were isolated from peripheral blood mononuclear cells (PBMCs). Human heart samples acquired from the left ventricular wall of explanted hearts following cardiac transplantation or obtained during implantation of left ventricular assist device. Samples were investigated for downstream analysis of protein by western blots, RNA quantification and cryo-sectioning. MI was induced in 9 to 12 weeks old male C57BL/6J mice, mice specifically lacking the cytoplasmic tail (CT) of TF (TFΔCT mice) and TFfl/flLysMCre+/− mice by permanent ligation of the left anterior descending artery. Left ventricular function was assessed by High-Frequency Ultrasound System. Infiltration of immune cells into the infarcted myocardium was analyzed by performing flow cytometric analysis after enzymatic digestion of the myocardium. Superoxide levels were quantified by HPLC-based measurement of dihydroethidium derived oxidation product 2-hydroxy ethidium.

Results

Circulating monocytes in patients with sub-acute MI showed increased nitrosative stress as well as increased phosphorylation of TF CT along with TGF-β1 and NF-kB inflammatory activation, which was recapitulated in cardiac tissue of end-stage heart failure patients with chronic MI. MI results in phosphorylation of the CT of TF within myeloid cells. Using mice with conditional knockout of TF on myeloid cells or TFΔCT mice, we found that this regulatory intracellular domain of TF within myeloid cells is required for cardiac infiltration of inflammatory Ly6Chigh TF+ monocytes, Rac-1 GTPase and superoxide formation of gp91phox + myeloid cells in MI. TGF-β1 dependent SMAD2 activation and cardiac collagen deposition as late sequel of MI was reduced in TFΔCT mice, resulting in attenuated cardiac dysfunction and reduced mortality.

Conclusion

We conclude that, TF CT drives NADPH-oxidase derived superoxide formation, thrombo-inflammation and cardiac fibrosis. Therefore, it might serve as putative biomarker and risk predictor in MI

Funding Acknowledgement

Type of funding source: None

Two-year clinical performance of Absorb BVS compared to Xience EES in ST-segment elevation myocardial infarction: a pooled analysis of AIDA and COMPARE-ABSORB trials

Introduction

Bioresorbable vascular scaffolds (BVS) use appears theoretically attractive in patients presenting with ST-segment elevation myocardial infarction (STEMI) as acute lesions are generally composed of soft plaques, in which optimal BVS deployment and expansion is easier to achieve. Furthermore, those patients are generally younger and would benefit longer from the promise of vascular restoration therapy.

Purpose

In this patient level pooled analysis of two clinical trials, we evaluated the clinical outcomes of Absorb BVS versus Xience everolimus-eluting stent (EES) in STEMI patients at 2-year follow-up.

Methods

We performed an individual patient-level pooled analysis of the AIDA and COMPARE-ABSORB trials in which 3515 patient were randomly assigned to Absorb BVS (n=1772) or Xience EES (n=1743). Clinical outcomes in STEMI patients were analyzed by randomized treatment assignment cumulative through 2 years. The primary efficacy outcomes measure was target lesion failure (cardiac death, target-vessel myocardial infarction or target lesion revascularization), and the primary safety outcome measure was device thrombosis at 2-year follow-up.

Results

350 (19.8%) STEMI patients were allocated to Absorb BVS versus 328 (18.8%) to Xience EES. The mean age of patient presenting with STEMI was 60 years old, 76.0% were males and 15.3% had diabetes mellitus. At 2-years target lesion failure occurred in 8.4% of BVS STEMI patients and 6.2% of EES STEMI patients (p=0.253). The 2-year rates of cardiac death (2.6% vs 1.6%, p=0.332), TV-MI (4.7% vs 2.5%) and TLR (6.8% vs 4.1%) were not significantly different. The 2-year incidence of definite device thrombosis was 4.7% in Absorb BVS versus 1.8% in Xience EES (p=0.045).

Conclusion

In the present patient-level pooled analysis of the AIDA and COMPARE-Absorb trials, BVS was associated with increased rates of device thrombosis in STEMI patients compared to Xience EES.

Funding Acknowledgement

Type of funding source: Private company. Main funding source(s): Abbott

Initial and long-term antithrombotic therapy after left atrial appendage closure with the WATCHMAN

Background

Evidence regarding post-procedural antithrombotic regimes other than used in randomized trials assessing percutaneous left atrial appendage (LAA) closure is limited.

Purpose

The present work aimed to compare different antithrombotic strategies applied in the real-world EWOLUTION study.

Methods

A total of 998 patients with successful WATCHMAN implantation at 47 centers were available for the present analysis. The composite ischemic endpoint of stroke, TIA, systemic embolism and device thrombus as well as the bleeding endpoint defined as at least major bleeding according to BARC were assessed during an initial period (from implant until first medication change) and long-term period (from first change until up to 2 years).

Results

The antithrombotic medication chosen in the initial phase was dual antiplatelet therapy (DAPT) in 60%, oral anticoagulation (OAC) in 27%, single antiplatelet therapy (SAPT) in 7% and no medication in 6%. In the long-term phase SAPT was used in 65%, DAPT in 23%, no therapy in 8% and OAC in 4%. No significant differences were found between the groups regarding the ischemic endpoint both in the initial period (Kaplan-Meier estimated rate 2.9% for DAPT vs. 4.3% for OAC vs. 3.9% for SAPT or no therapy; p=0.97) and in the second period (4.2% for SAPT vs. 1.8% for DAPT vs. 3.5% for no therapy; p=0.36). With respect to bleeding events the only difference was found in the initial phase with a higher incidence in patients under SAPT or no therapy (1.0% for DAPT vs. 0.8% for OAC vs. 7.4% for SAPT or no therapy; p=0.01). No differences in bleeding complications were observed during the second period (2.6% for SAPT vs. 2.9% for DAPT vs. 2.2% for no therapy; p=0.88).

Conclusions

Tailored antithrombotic treatment using even very reduced strategies such as SAPT or no therapy showed no significant differences regarding ischemic complications after LAA closure.

Funding Acknowledgement

Type of funding source: Private company. Main funding source(s): Boston Scientific

P2695ABSORB bioresorbable scaffold versus Xience metallic stent in acute coronary syndromes with treated with percutaneous coronary intervention. A subanalysis of the COMPARE-ABSORB trial

Background

The safety and efficacy of the ABSORB scaffold in ACS patients remain unclear. The COMPARE-ABSORB trial compares the ABSORB to the Xience stent in lesions and patients at high risk for restenosis Patients with STEMI and urgent PCI for non-STEMI were not excluded.

Methods

Patients included in the COMPARE-ABSORB trial undergoing PCI for ACS were eligible. Predefined implantation techniques for ABSORB was mandatory. Primary endpoint is target lesion failure (TLF) at 1 year, defined as a composite of cardiac death, target vessel myocardial infarction and clinically indicated target lesion revascularization.

Results

Of 1670 patients, 842 were treated for ACS. At 1-year, TLF occurred in 22 patients (5.0%) of the ABSORB group and in 14 patients (3.5%) of the Xience group (HR 1.44%; 95% CI 0.74%-2.82%, P=0.284). Definite device thrombosis occurred in 9 patients (2.0%) of the ABSORB group and in 2 patients (0.5%) of the Xience group (HR 4.10%; 95% CI 0.89%-18.9%, P=0.071).

Baseline characteristics ABSORB (n=442) XIENCE (n=400) Age, years (SD) 60.7 (9.6) 61.3 (9.1) Male 350/442 (79.2%) 313/400 (78.3%) Current smoker 159/439 (36.2%) 126/397 (31.7%) Diabetes mellitus 152/440 (34.5%) 138/399 (34.6%) Hypertension 298/442 (67.4%) 266/400 (66.5%) Hypercholesterolemia 255/442 (57.7%) 232/400 (58.0%) Family history of coronary artery disease 147/442 (33.3%) 103/400 (25.8%) Previous MI 61/442 (13.8%) 67/400 (16.8%) Established Peripheral Vascular Disease 27/442 (6.1%) 15/400 (3.8%) Previous PCI 83/442 (18.8%) 86/400 (21.5%) Previous CABG 1/442 (0.2%) 4/400 (1.0%) Previous stroke 15/442 (3.4%) 21/400 (5.3%) Renal Insufficiency 9/442 (2.0%) 13/400 (3.3%) Clinical presentation   Unstable angina 149/442 (33.7%) 141/400 (35.3%)   Non-ST elevation myocardial infarction 183/442 (41.4%) 156/400 (39.0%)   ST elevation myocardial infarction 110/442 (24.9%) 103/400 (25.7%)

KM plot for target lesion failure

Conclusion

The COMPARE-ABSORB trial showed no difference in the primary endpoint at one year for the ACS subgroup. The signal for increased thrombosis remained, even with the optimized implantation protocol

Acknowledgement/Funding

Maasstad Hospital, Rotterdam, the Netherlands

P2809Comparison between treatment of “established” versus complex “off-label” coronary lesions with Absorb bioresorbable scaffold implantation: results from the GABI-R registry

Objectives

The purpose of this study was to compare the clinical outcomes of patients treated with bioresorbable scaffold (BRS) for off-label versus approved indications.

Background

The BRS promised some advantages in terms of complete biodegradation, however, the implication of BRS for off-label indications is not well described.

Methods

The short- and long-term outcome after implantation of a bioresorbable scaffold system (ABSORB, Abbott Vascular, USA) was evaluated in the prospective, non-interventional, multicenter real-world German-Austrian ABSORB RegIstRy (GABI-R).

Results

A total of 3,188 patients were enrolled. Patients were divided into two groups: on-label BRS use (33.0%) and off-label use (66.9%) if at least one off-label use criteria was met. The incidence of scaffold thrombosis in confirmed cases was significantly higher in off-label group (1.36% vs. 0.57%, p=0.04; OR 2.41 (95% CI: 1.00–5.82) with also a trend towards higher myocardial infarction rate (2.39% vs. 1.42%, p=0.077; OR 1.70 (95% CI: 0.95–3.03) and cardiovascular death (1.27% vs. 1.14%, p=0.76, OR 1.11 (95% CI: 0.56–2.21) at 6 months follow up.

Clinical outcome at 6 months Total Off-label On-label p-value* OR (95%-CI) Patients with 6m FU record 99.0% 99.0% 99.1% 0.82 0.92 (0.43–1.95) Confirmed cardiovascular death 1.22% 1.27% 1.14% 0.76 1.11 (0.56–2.21) Confirmed non-cardiovascular death 0.22% 0.14% 0.38% 0.18 0.37 (0.08–1.66) Cause unknown 0.22% 0.28% 0.09% 0.29 2.97 (0.36–24.73) Hospitalisation 27.5% 27.9% 26.7% 0.51 1.06 (0.89–1.27) MI 2.07% 2.39% 1.42% 0.07 1.70 (0.95–3.03) ARC definite scaffold thrombosis 1.10% 1.36% 0.57% 0.04 2.41 (1.00–5.82) TLF 2.70% 3.00% 2.09% 0.13 1.45 (0.89–2.37) TVF 3.98% 4.31% 3.32% 0.18 1.31 (0.88–1.95) MACE 4.33% 4.64% 3.70% 0.22 1.27 (0.87–1.85) Values are mean ± standard deviation (SD) or number and percentage (n, %). *Comparison between off-label and on-label use. The p-values are from Chi-squared test or Mann-Whitney-Wilcoxon test. ARC, academic research consortium; FU, follow up; MACE, major adverse cardiac events; PCI, percutaneous coronary intervention; TLF, target lesion failure; TVF, target vessel failure.

Kaplan-Meyer curve stent thrombosis

Conclusions

The off-label use of BRS compared to confirmed indications appears to be associated with a higher rate of clinical endpoints considering more complex lesions and higher morbidity in this patients' group.

Acknowledgement/Funding

This research was supported by a grant from Abbott Vascular.

Secukinumab Reduces Endothelial Dysfunction in Subjects with Moderate-to-Severe Plaque Psoriasis Over 52 Weeks: Results of the Exploratory CARIMA Study

Abstract not available. Disclosures: Study sponsored by Novartis. Copyright 2018 SKIN

Admission heart rate in relation to presentation and prognosis in patients with acute myocardial infarction. Treatment regimens in German chest pain units

BACKGROUND

Higher heart rates on admission have been associated with poor outcomes in patients with an acute coronary syndrome in previous cohorts. Whether such a linear relationship still exists in contemporary high-level care is unclear.

METHODS

Prospectively collected data from patients presenting with myocardial infarction (MI) in centers participating in the Chest Pain Unit (CPU) Registry between December 2008 and July 2014 were analyzed. Patients were classified according to their initial heart rate (I: < 50; II: 50-69; III: 70-89; IV: ≥ 90 bpm). A total of 6,168 patients out of 30,339 patients presenting to 38 centers were included in the study.

RESULTS

Patients in group IV had more comorbidities, while patients in group I more often had a history of MI. Patients in the lowest heart rate group presented significantly earlier to the hospital (4 h 31 min vs. 7 h 37 min; p < 0.05) and had the highest rate of interventions. The overall survival after 3 months was significantly worse in group IV after adjusting for baseline variables. In the subgroup analysis, heart rate was a prognostic factor in the non-ST-segment elevation MI group but not in the ST-segment elevation MI group. The correlation between heart rate and major adverse cardiac events followed a J-shaped curve with worst outcomes in the lowest and highest heart rate groups.

CONCLUSION

Patients admitted to a dedicated CPU with the diagnosis of MI and a heart rate > 90 bpm experience reduced survival at 3 months despite optimal treatment. Patients with bradycardia also seem to be at increased risk for cardiovascular events despite much earlier presentation and treatment.

Porto-spleno-mesenteric venous thrombosis

Porto-spleno-mesenteric (PSM) venous thrombosis is a rare clinical condition that, while being mostly unrecognized, is nonetheless often severe with a high morbidity and mortality. PSM venous thrombosis is the cause of as many as 5-10% of all abdominal ischemic events, and it presents with a highly variable and non-specific pattern of abdominal symptoms. Such complex and non-specific presentation can delay diagnosis, determining the poor clinical outcome of this condition. This review article discusses the information available on the pathogenesis, clinical presentation, diagnosis and general management of PSM venous thrombosis, with a focus on a number of some clinical issues that remain unaddressed. In particular, the current understanding of the predisposing factors and the heterogeneous clinical manifestations of this condition are described in detail. The recent advances in imaging techniques, which are leading to an improved diagnostic accuracy and facilitate an early diagnosis are also presented. Further, the indications and limits of both pharmacological and surgical treatment options are discussed.

Assessment of vascular function: flow-mediated constriction complements the information of flow-mediated dilatation

OBJECTIVE

To determine whether vascular function assessed by low-flow-mediated constriction (L-FMC), a novel non-invasive method, complements the information obtained with "traditional" flow-mediated dilatation (FMD).

DESIGN AND PATIENTS

In protocol 1, 12 healthy young volunteers underwent FMD and L-FMC measurements at rest and immediately after isometric exercise of the same hand. In protocol 2, 24 patients with coronary artery disease, 24 with congestive heart failure, 24 hypertensive patients and 64 healthy volunteers were enrolled to undergo L-FMC and FMD measurements.

RESULTS

In protocol 1, exercise was associated with mean (SD) increases in radial artery blood flow, diameter and L-FMC (from -5.1 (1.5)% to -7.8 (3.4)%, p<0.05), while FMD was significantly blunted (from 6.0 (2.4)% to 3.0 (3.2)%, p<0.05). In protocol 2, both FMD and L-FMC were blunted in the patient groups. Receiver operating curve analysis showed that, as compared with FMD alone, the combination of L-FMC and FMD significantly improved the sensitivity and specificity in detecting patients diagnosed with cardiovascular disease (p<0.05).

CONCLUSION

In the first protocol, FMD and L-FMC were shown to be reciprocally regulated. A blunted FMD may, in certain cases, be an expression of increased resting vascular activation and not only of impaired endothelial function. In the second protocol, a statistical approach showed that implementation of L-FMC provides a better characterisation than FMD of vascular function in cardiovascular disease. Vascular (endothelial) function is a complex phenomenon which requires a multifaceted approach; it is suggested that a combination of L-FMC and FMD will provide additive and complementary information to "traditional" FMD measurements.

Area at risk and viability after myocardial ischemia and reperfusion can be determined by contrast-enhanced cardiac magnetic resonance imaging

BACKGROUND/AIMS

Clinical differentiation between infarcted and viable myocardium in the ischemic area at risk is controversial. We investigated the potential of contrast-enhanced cardiac magnetic resonance imaging (ceCMRI) in determining the area at risk 24 h after ischemia.

METHODS

Myocardial ischemia was induced by percutaneous coronary intervention of the left anterior descending coronary artery in pigs. Coronary occlusion time was 30 min in group A, which caused little myocardial infarction and 45 min in group B, which led to irreversible damage. 24 h after reperfusion ceCMRI was performed at 2 and 15 min after administration of gadolinium-diethylenetriamine pentaacetic acid. The area at risk was determined by intravenous injection of Evans blue and myocardial viability by triphenyltetrazolium-chloride staining.

RESULTS

The signal-intense areas at 2 and 15 min after contrast administration matched the area at risk in groups A and B. Nonviable myocardium in group A was overestimated (14-15%) while good agreement was present in group B.

CONCLUSION

The area at risk of reperfused ischemic myocardium can be determined by ceCMRI 24 h after coronary recanalization. This type of information might have relevant clinical implications in the treatment and stratification of patients with acute coronary syndrome in particular after surgical interventions.

Endothelium, ischemia and the good side of oxygen free radicals

Pathophysiological studies have clearly demonstrated that the relationship between endothelial (dys)function and tissue ischemia is bidirectional: while it is well accepted that endothelial dysfunction has a key role in the progression and the instabilization of coronary atherosclerosis, it is also well known that the endothelium is particularly sensitive to ischemia and reperfusion injury, and that this damage is an important component in determining the size of the infarction. Therefore, protecting the endothelium from ischemia has potentially important clinical implications. In this scenario, a particularly important role is played by reactive oxygen species: these elusive mediators are involved in determining the endothelial toxic effect of risk factors, are involved in reperfusion injury, but, most importantly, also have a role in endothelial preconditioning, a protective process that is characterized by a reduced sensitivity to ischemia and reperfusion. The present paper reports considerations regarding these phenomena as discussed in a lecture at the recent Conference of the European Society of Clinical Hemorheology and Microcirculation held in Dresden, Germany.

Evidence supporting abnormalities in nitric oxide synthase function induced by nitroglycerin in humans

OBJECTIVES

We studied the effects of nitroglycerin (GTN) therapy on the response to endothelium-dependent and independent vasoactive agents in the forearm circulation of healthy subjects.

BACKGROUND

Recent evidence suggests that therapy with GTN may induce specific changes in endothelial cell function, including increased superoxide anion production and sensitivity to vasoconstrictors. Additionally, continuous GTN therapy worsens endothelial function in the coronary circulation of patients with ischemic heart disease.

METHODS

Forearm blood flow was measured with venous occlusion, mercury-in-silastic strain gauge plethysmography.

RESULTS

Sixteen male volunteers (26 +/- 6 years) were randomized to no therapy (control) or GTN, 0.6 mg/h/24 h, for six days in an investigator-blind, parallel-design study. The flow responses to brachial artery infusions of acetylcholine ([Ach] 7.5, 15.0, 30.0 microg/min), N-monomethyl-L-arginine (L-NMMA) (1, 2, 4 micromol/min) and sodium nitroprusside (SNP) (0.8, 1.6, 3.2 microg/min) were recorded. The vasodilator responses to Ach were blunted in the GTN group as compared with the control group (p < 0.05). The vasoconstrictor responses to L-NMMA were also blunted in the GTN group (p < 0.001). In the GTN group, paradoxical vasodilation was observed in response to the lowest infused concentration of L-NMMA. The vasodilator responses to SNP did not differ between groups.

CONCLUSIONS

The response to Ach confirms the hypothesis that continuous GTN causes endothelial dysfunction. The responses to L-NMMA suggest that GTN therapy causes abnormalities in nitric oxide synthase (NOS) function; the vasodilation observed at the lowest infused concentration of L-NMMA in the GTN group also suggests that continuous GTN therapy is associated with a NOS-mediated production of a vasoconstrictor.

Folic acid prevents nitroglycerin-induced nitric oxide synthase dysfunction and nitrate tolerance: a human in vivo study

BACKGROUND

In healthy humans, continuous treatment with nitroglycerin (GTN) causes nitric oxide synthase dysfunction, probably through the reduced bioavailability of tetrahydrobiopterin. Recent studies proposed that folic acid is involved in the regeneration of tetrahydrobiopterin in different disease states. Therefore, we investigated whether folic acid administration would prevent this phenomenon. We also sought to determine if folic acid supplementation could prevent the development of tolerance to GTN.

METHODS AND RESULTS

On the first visit, 18 healthy male volunteers (aged 19 to 32 years) were randomized to receive either oral folic acid (10 mg once a day) or placebo for 1 week in a double-blind designed study. All subjects also received continuous transdermal GTN (0.6 mg/h). On the second visit, forearm blood flow was measured with venous occlusion strain gauge plethysmography in response to incremental infusions of acetylcholine (7.5, 15, and 30 microgram/min), N-monomethyl-L-arginine (1, 2, and 4 micromol/min), and GTN (11 and 22 nmol/min). Folic acid prevented GTN-induced endothelial dysfunction, as assessed by responses to intraarterial acetylcholine and N-monomethyl-L-arginine (P<0.01). Moreover, in the subjects treated with folic acid plus transdermal GTN, responses to intraarterial GTN were significantly greater than those observed after transdermal GTN plus placebo (P<0.05).

CONCLUSION

Our data demonstrate that supplemental folic acid prevents both nitric oxide synthase dysfunction induced by continuous GTN and nitrate tolerance in the arterial circulation of healthy volunteers. We hypothesize that the reduced bioavailability of tetrahydrobiopterin is involved in the pathogenesis of both phenomena. Our results confirm the view that oxidative stress contributes to nitrate tolerance.

Differential effects of pentaerythritol tetranitrate and nitroglycerin on the development of tolerance and evidence of lipid peroxidation: a human in vivo study

OBJECTIVES

We investigated the development of nitrate tolerance after continuous exposure to nitroglycerin (GTN) as compared with pentaerythritol tetranitrate (PETN) in humans.

BACKGROUND

Sustained therapy with GTN causes tolerance and has been associated with increased production of free oxygen radicals by the endothelium. Pentaerythritol tetranitrate is an organic nitrate that has been used in the therapy of angina. There have been no investigations concerning the development of tolerance to PETN in humans. Animal investigations suggested that continuous therapy with PETN does not cause increased free radical production or hemodynamic tolerance.

METHODS

We randomized 30 healthy volunteers to continuous GTN (0.6 mg/h/24 h), long-acting PETN (60 mg orally three times a day) or no treatment (control group) for seven days. We studied systemic blood pressure responses and venous volume responses to GTN with strain-gauge plethysmography. The levels of cytotoxic aldehydes and isoprostanes were measured as markers of free radical-mediated lipid peroxidation.

RESULTS

Tolerance, as demonstrated by blood pressure and forearm plethysmography, developed in the GTN group and was absent in the PETN group (p < 0.05). Therapy with GTN was associated with a significant increase in plasma markers of lipid peroxidation. This response was not observed in those treated with PETN (isoprostanes: control: 38 +/- 5; GTN: 59 +/- 6; PETN: 38 +/- 3 microg/ml; p < 0.005).

CONCLUSIONS

Treatment with PETN does not cause tolerance and is not associated with evidence of increased free radical production.