First-in-human experience of left atrial appendage occlusion with the steerable FuStar sheath.

BACKGROUND: Due the wide variability of left atrial appendage morphology left atrial appendage occlusion (LAAO) remains a challenging procedure. The steerable FuStar delivery sheath was designed to allow both, transseptal access and delivery of percutaneous devices. We here report the first-in-human experience of LAAO with the FuStar sheath. METHODS: Twenty patients (76.6 ± 8.4 years; 12 (60%) males; CHA2 DS2 -VASc score: 5.0 ± 2) with non-valvular fibrillation and contraindications to oral anticoagulation underwent LAAO with the LAmbre device using the FuStar steerable sheath (Lifetech Scientific Corp., Shenzhen, China) at two german centers. RESULTS: Successful device implantation was achieved in all patients (100%). No periprocedural complications were observed. Procedure time, fluoroscopy time, contrast media, and radiation dose were 23.4 min ± 9.2, 11.9 min ± 4.1, 96.2 mL ± 45.7, and 2718.4 cG*cm2 ± 3835.3, respectively. CONCLUSION: This study demonstrates the feasibility and safety of the steerable FuStar sheath for LAAO.

Coronary microvascular obstruction in acute myocardial infarction.

The success of a primary percutaneous intervention (PCI) in the setting of ST elevation myocardial infarction depends on the functional and structural integrity of coronary microcirculation. Coronary microvascular dysfunction and obstruction (CMVO) occurs in up to half of patients submitted to apparently successful primary PCI and is associated to a much worse outcome. The current review summarizes the complex mechanisms responsible for CMVO, including pre-existing coronary microvascular dysfunction, and highlights the current limitations in the assessment of microvascular function. More importantly, at the light of the substantial failure of trials hitherto published on the treatment of CMVO, this review proposes a novel integrated therapeutic approach, which should overcome the limitations of previous studies.

Acute myocardial infarction with no obstructive coronary atherosclerosis: mechanisms and management.

Myocardial infarction (MI) with no obstructive coronary atherosclerosis (MINOCA) is a syndrome with different causes. Its prevalence ranges between 5 and 25% of all MIs. The prognosis is extremely variable, depending on the causes of MINOCA. Clinical history, echocardiography, coronary angiography, and left ventriculography represent the first-level diagnostic investigations. Nevertheless, additional tests are required in order to establish its specific cause, thus allowing an appropriate risk stratification and treatment. We review pathogenesis, diagnosis, prognosis, and therapy of MINOCA and propose an algorithm for its management.

Plaque rupture and intact fibrous cap assessed by optical coherence tomography portend different outcomes in patients with acute coronary syndrome.

AIMS: Patients presenting with acute coronary syndrome (ACS) may have different plaque morphologies at the culprit lesion. In particular, plaque rupture (PR) has been shown as the more frequent culprit plaque morphology in ACS. However, its prognostic value is still unknown. In this study, we evaluated the prognostic value of PR, compared with intact fibrous cap (IFC), in patients with ACS. METHODS AND RESULTS: We enrolled consecutive patients admitted to our Coronary Care Unit for ACS and undergoing coronary angiography followed by interpretable optical coherence tomography (OCT) imaging. Culprit lesion was classified as PR and IFC by OCT criteria. Prognosis was assessed according to such culprit lesion classification. Major adverse cardiac events (MACEs) were defined as the composite of cardiac death, non-fatal myocardial infarction, unstable angina, and target lesion revascularization (follow-up mean time 31.58 ± 4.69 months). The study comprised 139 consecutive ACS patients (mean age 64.3 ± 12.0 years, male 73.4%, 92 patients with non-ST elevation ACS and 47 with ST-elevation ACS). Plaque rupture was detected in 82/139 (59%) patients. There were no differences in clinical, angiographic, or procedural data between patients with PR when compared with those having IFC. Major adverse cardiac events occurred more frequently in patients with PR when compared with those having IFC (39.0 vs. 14.0%, P = 0.001). Plaque rupture was an independent predictor of outcome at multivariable analysis (odds ratio 3.735, confidence interval 1.358-9.735). CONCLUSION: Patients with ACS presenting with PR as culprit lesion by OCT have a worse prognosis compared with that of patients with IFC. This finding should be taken into account in risk stratification and management of patients with ACS.

Effect of remote ischemic preconditioning on platelet activation and reactivity induced by ablation for atrial fibrillation.

BACKGROUND: Radiofrequency ablation of atrial fibrillation has been associated with some risk of thromboembolic events. Previous studies showed that preventive short episodes of forearm ischemia (remote ischemic preconditioning [IPC]) reduce exercise-induced platelet reactivity. In this study, we assessed whether remote IPC has any effect on platelet activation induced by radiofrequency ablation of atrial fibrillation. METHODS AND RESULTS: We randomized 19 patients (age, 54.7±11 years; 17 male) undergoing radiofrequency catheter ablation of paroxysmal atrial fibrillation to receive remote IPC or sham intermittent forearm ischemia (control subjects) before the procedure. Blood venous samples were collected before and after remote IPC/sham ischemia, at the end of the ablation procedure, and 24 hours later. Platelet activation and reactivity were assessed by flow cytometry by measuring monocyte-platelet aggregate formation, platelet CD41 in the monocyte-platelet aggregate gate, and platelet CD41 and CD62 in the platelet gate in the absence and presence of ADP stimulation. At baseline, there were no differences between groups in platelet variables. Radiofrequency ablation induced platelet activation in both groups, which persisted after 24 hours. However, compared with control subjects, remote IPC patients showed a lower increase in all platelet variables, including monocyte-platelet aggregate formation (P<0.0001), CD41 in the monocyte-platelet aggregate gate (P=0.002), and CD41 (P<0.0001) and CD62 (P=0.002) in the platelet gate. Compared with control subjects, remote IPC was also associated with a significantly lower ADP-induced increase in all platelet markers. CONCLUSIONS: Our data show that remote IPC before radiofrequency catheter ablation for paroxysmal atrial fibrillation significantly reduces the increased platelet activation and reactivity associated with the procedure.

Coronary functional tests in the catheterization laboratory - pathophysiological and clinical relevance.

Coronary angiography has long been the only diagnostic tool for the invasive assessment of coronary artery disease. Yet it does not allow establishing the functional severity of epicardial stenoses or vasomotor disorders of the epicardial arteries or coronary microcirculation. Functional tests in the catheterization laboratory have recently emerged as an important adjunct to coronary angiography for providing a comprehensive evaluation of the coronary circulation. In this review, we will describe and interpret the key functional tests used in current clinical practise in different clinical settings.

ST-segment elevation myocardial infarction ­ ideal scenario for bioresorbable vascular scaffold implantation?

Bioresorbable vascular scaffolds (BVS) represent a breakthrough technology for percutaneous coronary intervention (PCI). In this context, because of the unique properties of bioresorbable devices, ST-segment elevation myocardial infarction (STEMI) may represent the ideal scenario for BVS implantation. Consistently, 57% of physicians declare they currently use BVS in this group of patients. However, continuous and growing evidence on the good performance of these devices has been actually shown only in small studies with short- and mid-term follow-up. For these reasons, we need data from sufficiently large observational studies, with long-term follow-up, to confirm that BVS can deliver the same results as 2nd-generation drug-eluting stents when using an appropriate implantation technique. In this review, we discuss the potential advantages of BVS implantation in STEMI patients, together with the most recent evidence from clinical studies, highlighting safety and procedural concerns.

Protective effect of pre-infarction angina on microvascular obstruction after primary percutaneous coronary intervention is blunted in humans by cardiovascular risk factors.

BACKGROUND: Pre-infarction angina (PIA) has been shown to reduce the microvascular obstruction (MVO) rate in patients with ST-segment elevation myocardial infarction (STEMI). We sought to evaluate the potential modulator role of cardiovascular risk factors (CRFs) on this protective effect. METHODS AND RESULTS: Two hundred patients with STEMI were enrolled. PIA was defined as typical chest pain within the 48 h preceding STEMI onset. Angiographic MVO was defined as TIMI flow grade <2 or TIMI flow 3 with myocardial blush grade <2; electrocardiographic (ECG) MVO was defined as ST-segment elevation resolution <70%. Common CRFs were collected. In the absence of hypertension, both angiographic and ECG MVO rates were lower in patients with PIA as compared with those without, whereas, in the presence of hypertension, they were similar in both study groups (P for interaction=0.01 and P=0.014, respectively). Among nonsmokers, angiographic and ECG MVO rates were lower in patients with PIA as compared with those without, whereas within smokers, they were similar in both study groups (P for interaction=0.037 and P=0.037, respectively). In the absence of dyslipidemia, the angiographic and ECG MVO rates were lower in patients with PIA as compared with those without, whereas within dyslipidemic patients, they were similar in both study groups (P for interaction=0.012 and P=0.04, respectively). CONCLUSIONS: The protective effect of PIA on MVO is blunted by CRFs.

Management of vulnerable patient phenotypes and acute coronary syndrome mechanisms.

Atherosclerosis is a chronic vascular disease. Its prevalence increases with aging. However, atherosclerosis may also affect young subjects without significant exposure to the classical risk factors. Recent evidence indicates clonal hematopoiesis of indeterminate potential (CHIP) as a novel cardiovascular risk factor that should be suspected in young patients. CHIP represents a link between impaired bone marrow and atherosclerosis. Atherosclerosis may present with an acute symptomatic manifestation or subclinical events that favor plaque growth. The outcome of a plaque relies on a balance of innate and environmental factors. These factors can influence the processes that initiate and propagate acute plaque destabilization leading to intraluminal thrombus formation or subclinical vessel healing. Thirty years ago, the first autopsy study revealed that coronary plaques can undergo rupture even in subjects without a known cardiovascular history. Nowadays, cardiac magnetic resonance studies demonstrate that this phenomenon is not rare. Myocardial infarction is mainly due to plaque rupture and plaque erosion that have different pathophysiological mechanisms. Plaque erosion carries a better prognosis as compared to plaque rupture. Thus, a tailored conservative treatment has been proposed and some studies demonstrated it to be safe. On the contrary, plaque rupture is typically associated with inflammation and anti-inflammatory treatments have been proposed in response to persistently elevate biomarkers of systemic inflammation. In conclusion, atherosclerosis may present in different forms or phenotypes. Vulnerable patient phenotypes, identified by using intravascular imaging techniques, biomarkers, or even genetic analyses, are characterized by distinctive pathophysiological mechanisms. These different phenotypes merit tailored management.

Recurrent events after acute ST-segment elevation myocardial infarction: predictors and features of plaque progression and stent failure.

OBJECTIVES: Patients with acute ST-segment elevation myocardial infarction (STEMI) are at high risk for recurrent coronary events (RCE). Non-culprit plaque progression and stent failure are the main causes of RCEs. We sought to identify the incidence and predictors of RCEs. METHODS: Eight hundred thirty patients with STEMI were enrolled and followed up for 5 years. All patients underwent blood test analysis at hospital admission, at 1-month and at 12-month follow-up times. Patients were divided into RCE group and control group. RCE group was further categorized into non-culprit plaque progression and stent failure subgroups. RESULTS: Among 830 patients with STEMI, 63 patients had a RCE (7.6%). At hospital admission, HDL was numerically lower in RCE group, while LDL at both 1-month and 12-month follow-up times were significantly higher in RCE group. Both HDL at hospital admission and LDL at 12-month follow-up were independently associated with RCEs (OR 0.90, 95% CI 0.81-0.99 and OR 1.041, 95% CI 1.01-1.07, respectively). RCEs were due to non-culprit plaque progression in 47.6% of cases, while in 36.5% due to stent failure. The mean time frame between pPCI and RCE was significantly greater for non-culprit plaque progression subgroup as compared to stent failure subgroup (27 ±â€…18 months and 16 ±â€…14 months, P  = 0.032). CONCLUSION: RCEs still affect patients after pPCI. Low levels of HDL at admission and high levels of LDL at 12 months after pPCI significantly predicted RCEs. A RCE results in non-culprit plaque progression presents much later than an event due to stent failure.

Novel Medical Treatments and Devices for the Management of Heart Failure with Reduced Ejection Fraction.

Heart failure (HF) is a growing issue in developed countries; it is often the result of underlying processes such as ischemia, hypertension, infiltrative diseases or even genetic abnormalities. The great majority of the affected patients present a reduced ejection fraction (≤40%), thereby falling under the name of "heart failure with reduced ejection fraction" (HFrEF). This condition represents a major threat for patients: it significantly affects life quality and carries an enormous burden on the whole healthcare system due to its high management costs. In the last decade, new medical treatments and devices have been developed in order to reduce HF hospitalizations and improve prognosis while reducing the overall mortality rate. Pharmacological therapy has significantly changed our perspective of this disease thanks to its ability of restoring ventricular function and reducing symptom severity, even in some dramatic contexts with an extensively diseased myocardium. Notably, medical therapy can sometimes be ineffective, and a tailored integration with device technologies is of pivotal importance. Not by chance, in recent years, cardiac implantable devices witnessed a significant improvement, thereby providing an irreplaceable resource for the management of HF. Some devices have the ability of assessing (CardioMEMS) or treating (ultrafiltration) fluid retention, while others recognize and treat life-threatening arrhythmias, even for a limited time frame (wearable cardioverter defibrillator). The present review article gives a comprehensive overview of the most recent and important findings that need to be considered in patients affected by HFrEF. Both novel medical treatments and devices are presented and discussed.

Effect of exercise on circulating endothelial progenitor cells in microvascular angina.

BACKGROUND: Circulating endothelial progenitor cells (EPCs) might limit endothelial dysfunction in patients with microvascular angina (MVA). Endothelial colony-forming cells (ECFCs; displaying the CD34+/KDR+/CD45- phenotype) are currently regarded as true EPCs. The aim of this study was to evaluate exercise-induced ECFC mobilization and platelet reactivity in patients with MVA or with obstructive coronary artery disease (CAD). METHODS AND RESULTS: Exercise stress test (EST) was performed in 20 MVA patients, 20 CAD patients and 20 controls. Platelet reactivity was assessed before and after EST as formation of monocyte-platelet aggregates (MPAs) and CD41 platelet expression, without and with adenosine diphosphate (ADP) stimulation. ECFC number was measured before and 24h after EST. At rest, MPAs and CD41 platelet expression increased more with ADP in MVA patients (+71±11.0% and +37±7.5%, respectively), than in CAD patients (+37±8.6% and +19±4.5%, respectively) and controls (+29±3.5% and +21±3.1%, respectively; P<0.001 for both). At rest, ECFCs tended to be lower in CAD patients, compared to MVA patients and controls (4.1±5.0%, 7.2±6.0% and 7.3±7.0% cells/10(5), respectively; P=0.056). After EST, ECFCs increased less in MVA patients (+2.8±11) compared to CAD patients (+3.3±15; P<0.05) and controls (+7.4±24; P<0.01). CONCLUSIONS: In MVA patients, EST is able to blunt the peculiar increase of platelet reactivity to ADP present at rest; in contrast, no potential protective response of ECFCs to exercise was seen in these patients.

Cardiac Contractility Modulation Therapy in Patients with Amyloid Cardiomyopathy and Heart Failure, Case Report, Review of the Biophysics of CCM Function, and AMY-CCM Registry Presentation.

Cardiac amyloidosis may result in an aggressive form of heart failure (HF). Cardiac contractility modulation (CCM) has been shown to be a concrete therapeutic option in patients with symptomatic HF, but there is no evidence of its application in patients with cardiac amyloidosis. We present the case of TTR amyloidosis, where CCM therapy proved to be effective. The patient had a history of multiple HF hospitalizations due to an established diagnosis of wild type TTR-Amyloidosis with significant cardiac involvement. Since he was highly symptomatic, except during continuous dobutamine and diuretic infusion, it was opted to pursue CCM therapy device implantation. At follow up, a significant improvement in clinical status was reported with an increase of EF, functional status (6 min walk test improved from zero meters at baseline, to 270 m at 1 month and to 460 m at 12 months), and a reduction in pulmonary pressures. One year after device implantation, no other HF hospital admission was needed. CCM therapy may be effective in this difficult clinical setting. The AMY-CCM Registry, which has just begun, will evaluate the efficacy of CCM in patients with HF and diagnosed TTR amyloidosis to bring new evidence on its potential impact as a therapeutic option.

Association of heart rate variability with arrhythmic events in patients with arrhythmogenic right ventricular cardiomyopathy/dysplasia.

BACKGROUND: Arrhythmogenic right ventricular cardiomyopathy/dysplasia (ARVC/D) is associated with an increased risk of sudden cardiac death (SCD). Risk stratification of ARVC/D patients, however, remains an unresolved issue. In this study we investigated whether heart rate variability (HRV) can be helpful in identifying ARVC/D patients with increased risk of arrhythmic events. METHODS AND RESULTS: We studied 30 consecutive patients (17 males; 45.4 ± 18 years) with ARVC/D, diagnosed according to guideline criteria; 15 patients (50%) had received an implantable cardioverter defibrillator (ICD) for primary SCD prevention. HRV was assessed on 24-h ECG Holter monitoring. The primary endpoint was the occurrence of major arrhythmic events (SCD, sustained ventricular tachycardia (VT), ICD therapy for sustained VT or ventricular fibrillation (VF)). During the follow-up period (19 ± 7 months), no deaths occurred, but 5 patients (17%) experienced arrhythmic events (4 VTs and 1 VF, all in the ICD group). All HRV parameters were significantly lower in patients with, compared with those without, arrhythmic events. Low-frequency amplitude was the most significant HRV variable associated with arrhythmic events in univariate Cox regression analysis (P=0.017), and was the only significant predictor of arrhythmic events in multivariable regression analysis (hazard ratio 0.88, P=0.047), together with unexplained syncope (hazard ratio 16.1, P=0.039). CONCLUSIONS: Our data show that among ARVC/D patients HRV analysis might be helpful in identifying those with increased risk of major arrhythmic events.

Platelet reactivity and endothelial function in children of patients with early acute myocardial infarction.

AIMS: To assess whether platelet reactivity is increased in offspring of patients with early acute myocardial infarction (AMI) and its possible relation with endothelial dysfunction. METHODS AND RESULTS: We studied 23 healthy children (15±3 years, 13 males) of patients with early AMI (≤50 years old; Group 1) and 21 healthy children of healthy subjects without any history of cardiovascular disease (14±3 years, 10 males; Group 2). Platelet reactivity was assessed by flow cytometry as the increase in monocyte-platelet aggregates (MPA) and CD41 and PAC-1 platelet expression in response to exercise stress test (EST), adenosine diphosphate (ADP) stimulation (10(-7) M), or both. Endothelial function was assessed by measuring brachial artery dilation during post-ischaemic forearm hyperaemia [flow-mediated dilation (FMD)]. Both EST and ADP induced a higher percentage increase in platelet receptor expression in Group 1, compared with Group 2, with the most significant difference being shown for the response to the combined stimuli (e.g. MPA, 23.1±12 vs. 5.63±8%, P<0.001; platelet PAC-1, 57.7±47 vs. 13.2±7%, P<0.001). Compared with Group 2, Group 1 children showed lower FMD (10.7±3.1 vs. 8.0±2.9%, respectively; P=0.007). However, no significant association was found between FMD and platelet reactivity. CONCLUSION: Our results show increased platelet reactivity in children of patients with early AMI; the finding was not significantly correlated with endothelial dysfunction, suggesting that other mechanisms are mainly involved in the enhanced platelet response to agonistic stimuli.

Long-term Results of Perfusion-Balloon Valvuloplasty, Without Rapid Pacing, in High-Risk Elderly Patients With Severe Aortic Stenosis: A New Space Oddity.

BACKGROUND: Percutaneous balloon aortic valvuloplasty (BAV) is actually recommended as a bridge to surgery or transcatheter aortic valve replacement in patients with severe aortic stenosis (AS) in particular clinical settings. In this pilot study, for the first time, we report our experience utilizing a nonocclusive balloon for BAV, which does not require rapid ventricular pacing (RVP), in high-risk symptomatic elderly patients with severe AS. METHODS AND RESULTS: From 2018 to 2020, a total of 30 high-risk elderly patients with heart failure due to severe AS were treated with BAV and were all prospectively included in the study. We used a perfusion-balloon valvuloplasty without RVP (True Flow; BD/Bard). Hemodynamic parameters were invasively evaluated during catheterization, before and immediately after BAV. All patients were regularly followed to detect the rate of mortality. The patients were 87.56 ± 4.10 years old and 23% were males. In the catheterization laboratory, the peak left ventricular to aortic pressure gradient significantly decreased from 55 mm Hg (interquartile range [IQR], 48.75-66.25) to 26 mm Hg (IQR, 15.7-30) immediately after balloon inflation (P<.001). The median value of percentage decrease of transaortic gradient was 56% (IQR, 50-74). At a median of 12 months (IQR, 5-27) follow-up, 12 patients (40%) died. The median time between BAV and mortality was 10.5 months (IQR, 1.75-15.5). At multivariable analysis, the only predictor of mortality was the New York Heart Association class at admission (odds ratio, 3.29; 95% confidence interval, 2.4-298.4; P<.01). CONCLUSION: This single-center pilot study represents the first evidence that perfusion-balloon valvuloplasty without RVP is a safe, valid, and durable option in high-risk, symptomatic, elderly patients with severe AS.

Inflammation-related effects of adjuvant influenza A vaccination on platelet activation and cardiac autonomic function.

BACKGROUND: Inflammation, platelet reactivity and cardiac autonomic dysfunction increase the risk of cardiovascular events, but the relationships between these prognostic markers are poorly defined. In this study, we investigated the effect of an inflammatory stimulus (influenza A vaccine) on platelet activation and cardiac autonomic function. METHODS: We measured serum C-reactive protein (CRP) and interleukin-6 levels, monocyte-platelet aggregates (MPAs) and monocyte/platelet receptor expression before and after adjuvant influenza A vaccination in 28 patients with type II diabetes (mean age 62.1 ± 8 years, 18 men). Twenty-four-hour Holter electrocardiogram was recorded 24 h before and after vaccination; heart rate variability (HRV) was assessed as a measure of cardiac autonomic function. RESULTS: Inflammatory cytokines, MPA formation and monocyte/platelet receptor expression increased after vaccination. CRP was 2.6 ± 2.8 and 7.1 ± 5.7 mg L⁻¹ 48 h before and after vaccination, respectively (P < 0.0001). HRV parameters decreased after vaccination compared to baseline, with very low-frequency amplitude showing the most significant change (34.6 ± 11.8 and 31.0 ± 10.2 ms 48 h before and after vaccination, respectively; P = 0.002). A significant correlation was found between percentage changes in CRP levels and in most HRV variables, with the most significant correlations between changes in CRP levels and changes in standard deviation of all normal RR intervals (r = 0.43; P = 0.02). CONCLUSIONS: Together with an inflammatory reaction, influenza A vaccine induced platelet activation and sympathovagal imbalance towards adrenergic predominance. Significant correlations were found between CRP levels and HRV parameters, suggesting a pathophysiological link between inflammation and cardiac autonomic regulation. The vaccine-related platelet activation and cardiac autonomic dysfunction may transiently increase the risk of cardiovascular events.