Spontaneous pregnancy-associated coronary artery dissection: a case report on diagnostic and therapeutic challenges

Background

One of the main causes of myocardial infarction during pregnancy is spontaneous coronary artery dissection. This is ascribed to hormonal changes during pregnancy leading to a weakening of the vessel wall and haemodynamic changes especially during childbirth. Management options include conservative medical treatment and percutaneous coronary intervention, depending on clinical presentation.

Case summary

A 37-year-old woman presented with typical chest pain six weeks after giving birth to her third child. Echocardiography revealed a moderate reduction in systolic function. Initial invasive coronary angiography showed no abnormalities. After cardiac magnetic resonance demonstrated extensive scar, invasive coronary angiography was repeated including intravascular imaging. A dissection of the left anterior descending artery was visualized and treated by percutaneous coronary intervention and stenting. Left ventricular function was normalized at three-month follow-up. In this educational case report, we highlight the diagnostic and therapeutic challenges when treating this special patient cohort and the importance of cardiovascular imaging.

Discussion

Pregnancy-associated spontaneous coronary dissection is a potential differential diagnosis when treating post-partum women with recent onset chest pain. Management is challenging and intravascular imaging to visualize dissection should be performed during invasive coronary angiography. Patients require interdisciplinary care within a pregnancy heart team.

Long-Term Trajectories of Biomarkers, Functional, and Echocardiographic Parameters in Patients with Chronic Heart Failure from Dilated or Ischaemic Cardiomyopathy

INTRODUCTION

The long-term evolution of clinical, echocardiographic, and laboratory parameters of cardiac function in patients with chronic heart failure (HF) with either reduced (HFrEF) or mildly reduced (HFmrEF) left ventricular ejection fraction (LVEF) is incompletely characterised.

METHODS

We identified patients with chronic stable HF who presented at least twice to a university HF outpatient clinic between 1995 and 2021. Trajectories of NYHA functional class, LVEF, left ventricular internal end-diastolic diameter (LVIDD), NT-proBNP concentrations, and HF treatment over 10 years of follow-up were analysed using fractional polynomials. Analyses were repeated after stratifying patients according to aetiology (ischaemic vs. dilated) or HF category (HFrEF vs. HFmrEF).

RESULTS

A total of 2,132 patients were included, of whom 51% had ischaemic and 49% had dilated HF. Eighty six percent and 14% were classified as HFrEF and HFmrEF, respectively. Mean LVEF was 28 ± 10%, and median NT-proBNP and estimated glomerular filtration rate values were 1,170 (385-3,176) pmol/L and 81 (62-100) mL/min/1.73 m2, respectively. Median follow-up was 5.2 (2.6-9.2) years. Overall, NYHA functional class and LVIDD trajectories were U-shaped, whereas LVEF and NT-proBNP concentrations markedly improved during the first year and remained stable thereafter. However, the evolution of HF parameters significantly differed with respect to HF category and aetiology, with greater improvements seen in patients with HFrEF of non-ischaemic origin. Improvements in HF variables were associated with optimization of HF therapy, notably with initiation and up-titration of renin-angiotensin-system blockers.

CONCLUSION

This study provides insights into the natural history of HF in a large cohort of well-treated chronic HF outpatients with respect to subgroups of HF and different aetiologists.

Haemodynamic Effects of Sacubitril/Valsartan Initiation in Outpatients with Chronic Heart Failure

Background

Sacubitril/valsartan (S/V) improves outcomes in patients with heart failure with reduced ejection fraction (HFrEF). Data about the immediate, short-, and intermediate-term hemodynamic effects of S/V are limited.

Methods

In this prospective observational study, 37 outpatients with chronic HFrEF were treated with S/V according to current guideline recommendations. Next to clinical, laboratory and echocardiographic parameters, haemodynamic variables were assessed non-invasively by use of inert gas rebreathing and bioimpedance cardiography at baseline and at 2-week, 3-month and 6-month follow-up. The course of variables throughout the study and the relationship between variables were analysed using fractional polynomials.

Results

S/V treatment resulted in short- and intermediate-term improvements in NYHA functional class (2.3 ± 0.6 at baseline vs. 1.9 ± 0.5 at 6-month follow-up, p = 0.14), 6-min walk test (453 ± 110 vs. 528 ± 98 m, p = 0.02), ejection fraction (31 ± 9 vs. 36 ± 12%, p = 0.13), pulmonary artery pressure (39 ± 10 vs. 31 ± 10 mmHg, p = 0.02), and NT-proBNP values (1702 (782–2897 vs. 1004 (599–1627) ng/L, p = 0.03). In addition, S/V caused immediate decreases in systemic vascular resistance index (SVRI) and systolic blood pressure (SBP), which were associated with a simultaneous drop in stroke volume (SV) and cardiac index (CI). However, while SVRI and SBP remained at low levels during further treatment, SV and CI restored rapidly and increased to slightly higher levels thereafter.

Conclusion

The vasodilative effects of S/V result in immediate reductions in SVRI, SBP, SV and CI. However, S/V induces reverse cardiac remodelling, which is apparent shortly after treatment initiation and leads to improvements of clinical, functional, echocardiographic, laboratory and haemodynamic variables.

Supplementary Information

The online version contains supplementary material available at 10.1007/s40256-022-00549-2.

Coronary micro-computed tomography angiography in mice

Coronary computed tomography angiography is an established technique in clinical practice and a valuable tool in the diagnosis of coronary artery disease in humans. Imaging of coronaries in preclinical research, i.e. in small animals, is very difficult due to the high demands on spatial and temporal resolution. Mice exhibit heart rates of up to 600 beats per minute motivating the need for highest detector framerates while the coronaries show diameters below 100 μm indicating the requirement for highest spatial resolution. We herein use a custom built micro-CT equipped with dedicated reconstruction algorithms to illustrate that coronary imaging in mice is possible. The scanner provides a spatial and temporal resolution sufficient for imaging of smallest, moving anatomical structures and the dedicated reconstruction algorithms reduced radiation dose to less than 1 Gy but do not yet allow for longitudinal studies. Imaging studies were performed in ten mice administered with a blood-pool contrast agent. Results show that the course of the left coronary artery can be visualized in all mice and all major branches can be identified for the first time using micro-CT. This reduces the gap in cardiac imaging between clinical practice and preclinical research.

The need for dedicated advanced heart failure units to optimize heart failure care: impact of optimized advanced heart failure unit care on heart transplant outcome in high-risk patients

Aim

With an increasing prevalence of heart failure (HF), more patients with advanced disease have to be treated in cardiology units by sophisticated medical and interventional strategies. We therefore developed a dedicated advanced heart failure unit (AHFU) to target the specific needs of the many patients with advanced HF. We here present our concept and its impact on outcome in high‐risk high‐urgency (HU) heart transplant candidates.

Methods and results

The eight‐bed unit was established as an extension of the cardiologic intensive care and coronary care units in an intermediate care setting. Each bed was equipped with 24 h haemodynamic, respiratory, and arrhythmia monitoring. The unit is served 24/7 by five residents in cardiology, one staff cardiologist specializing in medical and interventional HF care, and 10 intensive care nurses. The cardiology team is supported by colleagues from cardiac surgery, sports medicine, psychosomatics, and the internal medicine departments. As an example of the intensified care on the AHFU, data from the cohorts of patients undergoing heart transplantation from HU status before (pre‐AHFU 2008–11) and after establishment of the AHFU (AHFU 2012–15) were analysed. Interestingly, mortality on HU waiting list and post‐heart transplant survival was comparable in both cohorts, despite significant increase in morbidity and co‐morbidity as assessed by the Index for Mortality Prediction After Cardiac Transplantation model in the AHFU group.

Conclusions

Our AHFU provides a unique and novel setting for the integration of modern pharmacological, interventional, surgical, and supportive HF therapy embedded in an academic heart centre. This may be a major step forward in the care of critical patients with advanced HF.

Physiological and unappreciated roles of CaMKII in the heart

In the cardiomyocyte, CaMKII has been identified as a nodal influencer of excitation-contraction and also excitation-transcription coupling. Its activity can be regulated in response to changes in intracellular calcium content as well as after several post-translational modifications. Some of the effects mediated by CaMKII may be considered adaptive, while effects of sustained CaMKII activity may turn into the opposite and are detrimental to cardiac integrity and function. As such, CaMKII has long been noted as a promising target for pharmacological inhibition, but the ubiquitous nature of CaMKII has made it difficult to target CaMKII specifically where it is detrimental. In this review, we provide a brief overview of the physiological and pathophysiological properties of CaMKII signaling, but we focus on the physiological and adaptive functions of CaMKII. Furthermore, special consideration is given to the emerging role of CaMKII as a mediator of inflammatory processes in the heart.

Abstract 433: Disrupting the Interaction Between CaM Kinase II and Histone Deacetylase 4 - an Epigenetic Therapy for Heart Failure?

CaM Kinase II (CaMKII) critically drives adverse cardiac remodeling. During the process of remodeling, CaMKII binds and phosphorylates Histone Deacetylase 4 (HDAC4), resulting in activation of the transcription factor MEF2. However, it remained unclear whether binding between CaMKII and HDAC4 causes heart failure and whether this interaction represents a novel therapeutic target. We used mouse genetics, HDAC4-based peptides and chemical biology to address these questions. First, we generated CaMKII-resistant HDAC4 mutant mice (CrH) by replacing Arg-598 (corresponds to Arg-601 in humans) of HDAC4 with Phe, because we found Arg-598 to be essential for the CaMKII-HDAC4 interaction. CrH were protected from cardiac dysfunction, hypertrophy and fibrosis in response to both pathological pressure overload or ischemia/reperfusion injury. CrH showed reduced CaMKII binding and less MEF2 activation. These data provided a proof-of-principle that the disruption of the CaMKII-HDAC4 interaction may have therapeutic potential. Thus, in a second step we engineered an HDAC4-derived peptide with homology to the CaMKII binding domain of HDAC4. This peptide competed with HDAC4 for binding with CaMKII, resulting in decreased MEF2 activation and attenuated agonist-induced cardiomyocyte hypertrophy. These data encouraged us to carry the translational pipeline one step further and we screened for small molecules that disrupt the CaMKII-HDAC4 interaction in an in vitro ALPHAScreen Assay (medium-throughput format using 78000 compounds). After a stringent validation process, 38 compounds showed > 40% inhibition. Out of these, 13 compounds effectively inhibited MEF2 activity in a cell-based assay without obvious signs for cellular toxicity, providing now potential cell permeable drug-like candidates. Chemical optimization and in vivo validation strategies are currently ongoing. In summary, we show that the CaMKII-HDAC4 interaction contributes to the development of heart failure and we identified drug-like molecules that specifically disrupt this protein-protein interaction. These findings lay the ground for a novel epigenetic therapeutic approach to combat heart failure.

CaM Kinase II mediates maladaptive post-infarct remodeling and pro-inflammatory chemoattractant signaling but not acute myocardial ischemia/reperfusion injury

CaMKII was suggested to mediate ischemic myocardial injury and adverse cardiac remodeling. Here, we investigated the roles of different CaMKII isoforms and splice variants in ischemia/reperfusion (I/R) injury by the use of new genetic CaMKII mouse models. Although CaMKIIδC was upregulated 1 day after I/R injury, cardiac damage 1 day after I/R was neither affected in CaMKIIδ-deficient mice, CaMKIIδ-deficient mice in which the splice variants CaMKIIδB and C were re-expressed, nor in cardiomyocyte-specific CaMKIIδ/γ double knockout mice (DKO). In contrast, 5 weeks after I/R, DKO mice were protected against extensive scar formation and cardiac dysfunction, which was associated with reduced leukocyte infiltration and attenuated expression of members of the chemokine (C-C motif) ligand family, in particular CCL3 (macrophage inflammatory protein-1α, MIP-1α). Intriguingly, CaMKII was sufficient and required to induce CCL3 expression in isolated cardiomyocytes, indicating a cardiomyocyte autonomous effect. We propose that CaMKII-dependent chemoattractant signaling explains the effects on post-I/R remodeling. Taken together, we demonstrate that CaMKII is not critically involved in acute I/R-induced damage but in the process of post-infarct remodeling and inflammatory processes.

Superior rejection profile during the first 24 months after heart transplantation under tacrolimus as baseline immunosuppressive regimen

Background

The use of tacrolimus (TAC) in patients after heart transplantation (HTX) has increased over the last few years.

Aim

In this retrospective study, we evaluated the effects of a TAC (conventional and extended-release TAC)-based immunosuppressive therapy regarding rejection profile in comparison to a cyclosporine A (CSA)-based regimen in patients after HTX.

Methods

The data of 233 patients who underwent HTX at the Heidelberg Heart Transplantation Center from May 1998 until November 2010 were retrospectively analyzed. Primary immunosuppressive therapy was changed from a CSA (n=114) to a TAC (n=119)-based regimen in February 2006 according to center routine. Follow-up period was 2 years post-HTX. Primary endpoint was time to first biopsy-proven rejection requiring therapy. In all patients, routine follow-up at the Heidelberg Heart Transplantation Center was mandatory.

Results

Multivariate risk factor analysis regarding time to first rejection episode showed no statistically significant differences regarding recipient age, donor age, recipient sex, donor sex, sex mismatch, ischemic time, and diagnosis leading to HTX between the two groups (all P= not statistically significant). Time to first biopsy-proven rejection was significantly longer in the TAC group (intention-to-treat analysis, n=233, log-rank test P<0.0001; per-protocol analysis, n=150, log-rank test P=0.0003). In patients who underwent a change of primary immunosuppression (n=49), a significantly longer time to first biopsy-proven rejection was also found in the primary TAC subgroup (log-rank test P=0.0297). Further subgroup analysis in the TAC subgroups showed no statistically significant differences in time to biopsy-proven rejection under extended-release TAC compared to conventional TAC (intention-to-treat analysis, log-rank test P=0.1736).

Conclusion

Our study demonstrated that a TAC-based primary immunosuppressive therapy is superior to a CSA-based immunosuppressive regimen in patients after HTX regarding time to first biopsy-proven rejection.