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Objectives. Coronary revascularisation and intra-aortic balloon pump (IABP) has been considered the gold standard treatment of acute coronary syndrome with cardiogenic shock, recently challenged by...

This is the pre-peer reviewed version of the following article: Solberg, O., Stavem, K., Ragnarsson, A., Beitnes, J., Skårdal, R., Seljeflot, I., ... Aaberge, L. (2019). Index of microvascular resistance to assess the effect of rosuvastatin on microvascular function in women with chest pain and no obstructive coronary artery disease: A double‐blind randomized study. Catheterization and Cardiovascular Interventions, 94(5), 660-668., which has been published in final form at https://doi.org/10.1002/ccd.28157. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Use of Self-Archived Versions. Introduction - Many women undergoing coronary angiography for chest pain have no or only minimal coronary artery disease (CAD). However, despite the lack of obstructive CAD, they still have an increased risk of major adverse cardiovascular events. Pleiotropic effects of statins may influence microvascular function, but if statins improve microvascular function in unselected chest pain patients is not well studied. This study assessed microvascular function by using the thermodilution‐derived test “the index of microvascular resistance” (IMR) with the aim of determining the (i) IMR level in women with chest pain and non‐obstructive CAD and if (ii) IMR is modified by high‐dose statin treatment in these patients. Additional objectives were to identify the influence of statins on the health status as assessed with generic health questionnaires and on biomarkers of endothelial activation. Materials and methods - The study was a randomized, double‐blind, single‐center trial comparing 6 months of rosuvastatin treatment with placebo. In total, 66 women without obstructive CAD were included. Mean age was 52.7 years and 55.5 years in the placebo and rosuvastatin group, respectively. Microvascular function was assessed using the IMR, health status was assessed using the SF‐36 and EQ‐5D questionnaires, and biochemical values were assessed at baseline and 6 months later. Results and conclusions - In the placebo group IMR was 14.6 (SD 5.7) at baseline and 14.4 (SD 6.5) at follow‐up. In the rosuvastatin group IMR was 16.5 (SD 7.5) at baseline and 14.2 (SD 5.8) at follow‐up. IMR did not differ significantly between the two study groups at follow‐up controlled for preintervention values. C‐reactive protein (CRP) was comparable between the groups at baseline, while at follow‐up CRP was significantly lower in the rosuvastatin group compared to placebo [0.6 (±0.5) mg/L vs. 2.6 (±3.0) mg/L; p = 0.002]. Whereas rosuvastatin treatment for 6 months attenuated CRP levels, it did not improve microvascular function as assessed by IMR (Clinical Trials.gov NCT 01582165, EUDRACT 2011‐002630‐39.3tcAZ).

Background Chronic thromboembolic pulmonary hypertension (CTEPH) induces right ventricular (RV) adaptive changes but often results in RV failure and death. Balloon pulmonary angioplasty (BPA) is a treatment option in patients in whom pulmonary endarterectomy is contraindicated and in patients with residual pulmonary hypertension after pulmonary endarterectomy. We hypothesized that RV reverse remodeling and improved RV function would occur after BPA in patients with CTEPH. Methods In 26 patients with CTEPH (59 ± 12 years old; 11 men), echocardiography, cardiopulmonary exercise testing, blood samples, and right-sided cardiac catheterization were performed before and after 4 ± 2 BPA procedures. Echocardiography images were analyzed off-line with particular focus on RV function according to current recommendations. Differences from baseline to follow-up were analyzed by paired samples t tests. Results Significant improvements in hemodynamics, peak oxygen consumption, and levels of N-terminal pro-B-type natriuretic peptide were detected after BPA. All measures of RV function improved considerably, including fractional area change (+6%; p = 0.003), tricuspid annular plane systolic excursion (+3 mm; p p = 0.002). RV end-diastolic diameter, area, and free wall thickness decreased significantly, whereas left ventricular diameter and stroke volume increased. Conclusions After BPA, a significant improvement in RV functional parameters could be observed by echocardiography, adding credibility to this form of treatment in patients with CTEPH.

Objectives The objectives of the present study were to compare a simplified and a comprehensive method of estimating the index of microvascular resistance (IMR) and assess the changes from 7-11 weeks to 1 year after heart transplant (HTx). Background he IMR is specific to the microvasculature and reflects the status of the microcirculation in cardiac patients and can be estimated via a simplified method (IMR(s)) or a comprehensive method (IMR(c)). The calculation for the latter includes coronary wedge pressure and central venous pressure. Methods Consecutively transplanted patients (n = 48) underwent left and right heart catheterization including physiological evaluation at two time points post-HTx. The agreement between the values of IMR obtained using the IMR(s) and IMR(c) methods were assessed using Bland-Altman analysis. The agreements and differences were assessed using mixed model analysis. Results The mean bias between IMRs and IMRc was 1.3 mm Hg·s (95% limits of agreement: -1.2, 3.8 mm Hg). Between 7-11 weeks and 1 year post-HTx there was a significant decline in IMR(s) values (P = 0.03) but a smaller and statistically nonsignificant decline in IMR(c) values (P = 0.13). The significant difference (P = 0.04) between IMR(c) and IMR(s) 7-11 weeks post-HTx was no longer present at 1 year (P = 0.24). Conclusions The IMR(s) method resulted in slightly higher IMR estimates and exhibited a somewhat larger change over the 10-month follow-up period than the IMR(c) method. However, the differences between the methods were small and unlikely to be of clinical importance.

Aims The index of microvascular resistance (IMR) is a relatively new tool that is used to assess microvascular function during routinely performed left heart catheterisations. In order to establish a reference interval for IMR, we investigated a subset of arrhythmia patients with structurally normal hearts and no or minimal coronary artery disease. Methods and results Physiological variables, including IMR, were measured in 20 otherwise healthy patients aged 40-60 years (10 males and 10 females) who had been referred for electrophysiological evaluation of suspected atrioventricular nodal re-entry tachycardia. IMR values were non-normally distributed with a median value of 12.6. We established a reference interval, that would be relevant to 95% of the population, of 7.3 (90% CI: 6.6-8.0) - 27.2 (90% CI: 20.8-33.7), using Box-Cox transformation and the robust Horn method. Spearman's rank correlation analysis revealed no significant relationship between IMR and several different variables. Conclusions A reference interval for IMR was established in a population of patients aged 40-60 years with structurally normal hearts, considered to be representative of the general population. IMR was not related to sex, age or any of the other variables tested, suggesting that this reference range can be applied to the general population.

In this 12-month multicenter Scandinavian study, 78 maintenance heart transplant (HTx) recipients randomized to everolimus with reduced calcineurin inhibitor (CNI) exposure or continued standard CNI-therapy underwent matched virtual histology (VH) examination to evaluate morphological progression of cardiac allograft vasculopathy (CAV). Parallel measurement of a range of inflammatory markers was also performed. A similar rate of quantitative CAV progression was observed in the everolimus (n = 30) and standard CNI group (n = 48) (plaque index 1.9 ± 3.8% and 1.6 ± 3.9%, respectively; p = 0.65). However, VH analysis revealed a significant increase in calcified (2.4 ± 4.0 vs. 0.3 ± 3.1%; p = 0.02) and necrotic component (6.5 ± 8.5 vs. 1.1 ± 8.6%; p = 0.01) among everolimus patients compared to controls. The increase in necrotic and calcified components was most prominent in everolimus patients with time since HTx >5.1 years and was accompanied by a significant increase in levels of von Willebrand (vWF) factor (p = 0.04) and vascular cell adhesion molecule (VCAM) (p = 0.03). Conversion to everolimus and reduced CNI is associated with a significant increase in calcified and necrotic intimal components and is more prominent in patients with a longer time since HTx. A significant increase in vWF and VCAM accompanied these qualitative changes and the prognostic implication of these findings requires further investigation.

SummaryActivated platelets release a wide range of inflammatory mediators, including members of the tumour necrosis factor (TNF) superfamily (e.g. CD40 ligand [CD40L] and LIGHT). Such platelet-mediated inflammation could be involved in atherogenesis and plaque destabilisation. In the present study we investigated whether APRIL, another member of the TNF superfamily that has been detected in megakaryocytes, could be released from platelets upon activation. The release of APRIL was studied in thrombin receptor (SFLLRN) activated platelets, and the expression of APRIL was examined in plasma and within the atherosclerotic lesion in patients with carotid and coronary atherosclerosis. Upon SFLLRN activation, there was a gradual release of APRIL, reaching maximum after 90 minutes. While this pattern is similar to that of CD40L and LIGHT, the release of APRIL was quite differently regulated. Thus, prostaglandin E1,but not inhibitors of metal-dependent proteases and actin polymerisation or the lack of GP IIb/IIIa, blocks APRIL release in activated platelets. With relevance to atherogenesis, we found that patients with coronary artery disease (n=80) had raised plasma levels of APRIL as compared with controls (n=20), and APRIL immunoreactivity was detected in aggregated platelets within the ruptured plaque in patients with myocardial infarction and within macrophages in symptomatic carotid plaques. In conclusion, activated platelets release significant amounts of APRIL in a longlasting manner, differently regulated than the gradual release of other platelet-derived TNF superfamily ligands. The enhanced expression of APRIL in atherosclerotic disorders, both systemically and within the lesion, may suggest a potential involvement of APRIL in atherogenesis.

Background Microvascular function in transplanted hearts can be evaluated by methods used in routine left heart catheterization follow-up after heart transplantation (HTx). This sub-study of a randomized study compared the effects of everolimus (EVR) and calcineurin inhibitor (CNI) treatment on microvascular function as expressed by the index of microvascular resistance (IMR) at 1 year after HTx. A secondary objective was to compare the change in IMR from 7–11 weeks to 1 year after HTx between randomized groups. Methods There were 70 HTx recipients included and randomly assigned to combination therapy (EVR and CNI with early CNI withdrawal) vs conventional CNI treatment. Coronary physiologic assessment was performed 7–11 weeks and 1 year after HTx. A linear mixed model was used to assess the group difference at 1 year and the difference in IMR change between 7–11 weeks and 1 year after HTx. Results At 1 year, there was no significant difference in IMR between the EVR group (17.5 mm Hg∙sec ± 8.9) (mean ± SD) and the CNI group (14.9 mm Hg∙sec ± 6.6, p = 0.17). The difference in IMR change between the 2 treatment arms was 1.6 mm Hg∙sec (95% confidence interval, −2.8 to 5.9; p = 0.49). Spearman's rank correlation coefficient at 1 year after HTx between IMR and maximal intimal thickness as assessed with intravascular ultrasound in the left anterior descending artery was −0.13 ( p = 0.28). Conclusions In this prospective, open, randomized study comparing early CNI withdrawal with mammalian target of rapamycin inhibitors immunosuppression during the first year after HTx, early transition from CNI-based immunosuppression to EVR-based treatment did not result in differences in microvascular function as assessed by the IMR.

The objectives of the present study were to compare a simplified and a comprehensive method of estimating the index of microvascular resistance (IMR) and assess the changes from 7-11 weeks to 1 year after heart transplant (HTx).he IMR is specific to the microvasculature and reflects the status of the microcirculation in cardiac patients and can be estimated via a simplified method (IMR(s)) or a comprehensive method (IMR(c)). The calculation for the latter includes coronary wedge pressure and central venous pressure.Consecutively transplanted patients (n = 48) underwent left and right heart catheterization including physiological evaluation at two time points post-HTx. The agreement between the values of IMR obtained using the IMR(s) and IMR(c) methods were assessed using Bland-Altman analysis. The agreements and differences were assessed using mixed model analysis.The mean bias between IMRs and IMRc was 1.3 mm Hg·s (95% limits of agreement: -1.2, 3.8 mm Hg). Between 7-11 weeks and 1 year post-HTx there was a significant decline in IMR(s) values (P = 0.03) but a smaller and statistically nonsignificant decline in IMR(c) values (P = 0.13). The significant difference (P = 0.04) between IMR(c) and IMR(s) 7-11 weeks post-HTx was no longer present at 1 year (P = 0.24).The IMR(s) method resulted in slightly higher IMR estimates and exhibited a somewhat larger change over the 10-month follow-up period than the IMR(c) method. However, the differences between the methods were small and unlikely to be of clinical importance.

To the Editor: Intracoronary injection of bone marrow cells (BMC) has been introduced for improvement of left ventricular (LV) function after acute myocardial infarction (AMI). In the randomized ASTAMI (Autologous Stem cell Transplantation in Acute Myocardial Infarction) study, BMC treatment did not

Coronary physiologic methods like coronary flow reserve, fractional flow reserve and the index of microvascular resistance (IMR) have emerged as complementary methods to angiography and intravascular ultrasound for assessing the physiological status of the coronary vasculature in heart transplant (

To examine the effect of balloon pulmonary angioplasty (BPA) on chronic thromboembolic pulmonary hypertension (CTEPH) in patients with inoperable disease or persistent pulmonary hypertension after pulmonary endarterectomy.Observational cohort study.Referred patients with inoperable or persistent CTEPH.Twenty consecutive CTEPH patients (10 females), aged 60±10 years.Right heart catheterisation, functional capacity (cardiopulmonary exercise testing (CPET) and NYHA class) and blood sampled biomarkers N-terminal pro-brain natriuretic peptide (NT-proBNP) and troponin T examined at the time of diagnosis and repeated in all patients 3 months after the last BPA.Seventy-three catheterisations were performed with 18.6±6.1 BPAs per patient on segmental and subsegmental arteries. Two deaths occurred following the first BPA, with an overall 10% periprocedural death rate. Reperfusion oedema complicated seven procedures. Comparisons before and after BPA showed significant haemodynamic improvements, including decreased mean pulmonary artery pressure (mPAP) (45±11 mm Hg vs 33±10 mm Hg; p0.001) and increased cardiac output (4.9±1.6 L/min vs 5.4±1.9 L/min; p=0.011). Reduced right ventricular strain was indicated by significantly lower plasma levels of NT-proBNP and troponin T. Significant improvement in functional capacity was evident as assessed by NYHA class (3.0±0.5 vs 2.0±0.5; p0.001) and CPET (13.6±5.6 mL/kg/min vs 17.0±6.5 mL/kg/min; p0.001). Seventeen patients (85%) were alive after 51±30 months of follow-up.BPA may offer an alternative form of treatment in selected CTEPH patients. While prognostic markers such as haemodynamics, functional capacity and biomarkers improve, significant periprocedural complications must be recognised. Randomised trials are warranted.

We thank Drs Sengupta and colleagues for their interest in our work.1 Our aim was to understand what causes the pre- and postejection velocity spikes. The main focus of Sengupta et al is to understand why the spikes sometimes cross the zero line, a phenomenon that they name biphasic spikes , as it denotes both a shortening phase (positive velocity) and a lengthening phase (negative velocity). This is an interesting topic, but it was outside the scope of our study.1 The preejection velocity has a spike shape, ie, an upstroke and a downstroke. The upstroke from zero reflects the start of shortening, which pushes blood toward the valve plane and closes the mitral valve. Mitral valve closure then …

Background— Normal left ventricular myocardium demonstrates distinct spikes in the velocity trace before and after left ventricular ejection. We tested the hypothesis that the preejection and postejection velocity spikes reflect early systolic shortening and late systolic lengthening that are interrupted by mitral and aortic valve closure, respectively. Methods and Results— In 11 anesthetized dogs, timing of valve closure was determined by pressure variables; left ventricular dimensions were determined by sonomicrometry. Myocardial shortening started 20±10 ms (mean±SD; P P P =0.036), indicating that preejection shortening was larger with a leaking valve. Similarly, late systolic lengthening was reduced in patients (n=15) with severe aortic regurgitation after prosthetic valve replacement; minimum postejection velocity spike was increased from −32±11 to −17±11 mm/s; P =0.0003). Asynchronous onset of contraction/relaxation and atrioventricular interaction were investigated as alternative mechanisms of the velocity spikes in dogs and patient groups but were found implausible. Conclusions— This study supports the hypothesis that normal left ventricular preejection and postejection velocity spikes are attributed to valve closures that interrupt early systolic shortening and late systolic lengthening, respectively.

A 77-year-old woman suffering from progressive dyspnea and chest pain for 2 1/2 years was admitted to hospital. There were no ECG changes at exercise test and a dobutamine stress echocardiography was normal. At catheterization, right-sided pressures were within normal limits. Coronary angiography revealed a congenital coronary fistula, 3-4 mm in diameter, from the left anterior descending artery to the proximal pulmonary artery. There was no significant rise in blood oxygen saturation in the pulmonary artery. Transcatheter coil embolization was performed in the distal part of the tortuous fistula. Flow ceased within minutes, demonstrating the feasibility and efficacy of this technique for treating large fistulas.

Routine angio-guided stent deployment results in a relatively high restenosis rate, which is mostly due to stent sub-expansion. Several different intravascular ultrasound (IVUS) criteria for optimal stent deployment have been proposed. A minimal in-stent restenosis and a minimal in-stent lumen area ofor = 9 mm2 have been associated with low rates of restenosis and target lesion revascularization (TLR) at 6 months. The role of high-pressure stent deployment and/or upsizing the post-dilatation balloon has not yet been clarified. The aim of this study was to evaluate the possibility of achieving accepted IVUS criteria safely without IVUS guidance with the combination of high-pressure deployment and post-dilatation with a 0.25 mm oversized balloon.Thirty-four stents (26 NIR, 3 AVE GFX, 3 ACS GFX, 1 Bard, 1 Jostent) were implanted in 30 patients until optimal angiographical results were obtained (10% residual stenosis visually). Forty percent of the patients had unstable angina pectoris, forty-four percent had complex lesions (B2 and C) and 29% were occlusions. Mean inflation pressure was 12.6 +/- 1.6 atm, mean stent diameter was 3.2+/- 0.4 mm and mean stent length was 15.1+/- 5.4 mm. Post-dilatation was performed with the same stent using a short (compared to the angiographic reference segment), 0.25 mm oversized Scimed Maxxum Energy 3.5 +/- 0.4 mm balloon using high pressure (16.1 +/- 1.7 atm) followed by an off-line IVUS examination of the stents. There was clinical follow-up for 1 year. Results in patients with single-vessel disease were compared with those of non-randomized controls, who were stented with high pressure but without over-dilatation.No stent achieved the nominal diameter, in spite of over-dilatation. Mean minimal stent diameter (MLD) according to IVUS was 2.9 +/- 0.4 mm (92% of the angiographic reference diameter). Mean minimal lumen area (MLA) was 7.7 +/- 2.2 mm2. An in-stent MLAor = 90% of the distal reference segment (AVID criteria) and an MLAor = 100% oror = 90% of the smallest/average reference segment (MUSIC criteria) was found in 67% and 57%, respectively. MLAor = 9 mm2 was achieved in 38%. All stents had good apposition and obtained a symmetry indexor = 0.7 mm. No acute perforations, dissections or other serious complications occurred during the over-dilatation. At 1 year, five patients had re-angina leading to a new coronary angiography; only 1 patient had a significant in-stent restenosis requiring re-PTCA. Compared to non-overdilated historical controls, the standardized over-dilatation seemed to give a larger MLD (3.0 +/- 0.4 mm vs. 2.7 +/- 0.4 mm; p = 0.03), more patients who fulfilled AVID criteria (70% vs. 32%; p = 0.048) and more stents with MLAor = 9 mm2 (46% vs. 11%; p = 0.02).A standardized 0.25 mm over-dilatation of stents never achieved nominal stent size, but did improve lumen gain and was associated with low target vessel revascularization without adding complications to the routine stenting procedure.

Purpose Immunosuppressant regimes centered on everolimus have been demonstrated to provide a quantitative reduction in cardiac allograft vasculopathy (CAV) amongst de-novo heart transplant (HTx) recipients. However, the effect of such therapy on CAV assessed by the qualitative method of Virtual Histology (VH) is unknown and was investigated in this prospective randomized-controlled trial. Methods and Materials In this 12-month multicenter Scandinavian study 190 maintenance HTx recipients were randomized to everolimus with reduced calcineurin inhibitor (CNI) exposure or continue standard CNI-therapy. Both groups continued their prior usage of azathioprine (AZA) or mycophenolate mofetil (MMF). 78 patients had evaluable VH examinations at baseline and 12 months and matched analysis was performed to measure change in fibrotic, fibrofatty, calcified and necrotic tissue component. Results When considering all 78 patients, mean age 57.4±10.3 years and mean time post-HTx 5.4±4.1 yrs, a similar rate of quantitative CAV progression was observed in the everolimus (n=30) versus standard CNI therapy group (n=48) (plaque index 1.9±3.9% and 1.6±3.7%, respectively; p=0.65). Virtual Histology analysis revealed a significant increase in calcified (2.4±4.0 versus 0.3±3.1%; p=0.02) and necrotic component (6.4±8.5 versus 1.0±8.6%; p 0.05). Conclusions Conversion to everolimus and reduced CNI does not significantly influence quantitative progression of CAV but is associated with a significant increase in calcified and necrotic tissue component. The prognostic implication of these qualitative changes in HTx recipients is unclear and warrants further investigation.