Acute myocardial infarction in adolescents: reappraisal of underlying mechanisms.

Worldwide, a myocardial infarction (MI) is an important cause of death. Acute MI occurs most commonly at an older age. However, the incidence of acute MI in adolescents is increasing. This is partly due to an increase in cardiovascular risk factors (e.g. smoking, unhealthy diet), which might lead to premature atherosclerosis. However, several non-atherosclerotic causes of MI in adolescents are also described in the literature, such as vascular spasm due to the use of cocaine. We may assume that acute MI is not considered to be the most likely cause of chest pain in adolescents. Therefore, the risk of a dramatic outcome in this patient category may be significant. This point of view article addresses the pathophysiological process and subsequent diagnostic approach in adolescents with MI resulting from either premature atherosclerosis or of non-atherosclerotic causes. Insight into the potential operational mechanisms of the coronary artery incident may have a major impact on the clinical course following admission. We would like to underline that a personalised clinical approach remains of utmost importance in each patient treated by protocolised medicine. This is particularly true when acute MI occurs at a young age, since the underlying cause more frequently differs from the conventional atherosclerotic process in this patient category.

The 1­year safety and efficacy outcomes of Absorb bioresorbable vascular scaffolds for coronary artery disease treatment in diabetes mellitus patients: the ABSORB DM Benelux study.

BACKGROUND: Diabetes mellitus (DM) patients show higher rates of repeat revascularisation even in the era of modern drug-eluting stents (DES). The concept of bioresorbable scaffolds is becoming captivating, as it might allow for repeat interventions, prolonging the time span during which patients can be treated by percutaneous coronary intervention (PCI). AIMS: We intend to evaluate the short- and long-term safety and efficacy of Absorb bioresorbable vascular scaffolds (Absorb BVS) in the treatment of coronary artery disease (CAD) in DM patients for any indication. METHODS: The ABSORB DM Benelux is an international prospective study in DM patients who have undergone PCI with ≥1 Absorb BVS. Major adverse cardiac events (MACE) at 1 year was the primary endpoint, defined as a composite of all-cause death, any myocardial infarction (MI) and ischaemia-driven target vessel revascularisation (TVR). Secondary endpoints were target lesion failure (TLF) and definite or probable scaffold thrombosis (ScT). RESULTS: Between April 2015 and March 2017, 150 DM patients and 188 non-complex lesions were treated. Device implantation was successful in 100%. MACE occurred in 14 (9.5%) patients, with all-cause death occurring in 4 (2.7%), any MI in 6 (4.1%) and ischaemia-driven TVR in 7 (4.8%) respectively. TLF was reported in 11 (7.5%). Definite and probable ScT was observed in 2 (1.4%). CONCLUSION: Absorb BVS for treatment of anatomically low-risk patients with DM show acceptable safety and efficacy outcomes at 1 year. If these promising results are confirmed after a longer follow-up period, new-generation bioresorbable scaffolds combined with refinement of implantation techniques might open new horizons for CAD treatment in DM patients.

Everolimus-eluting bioresorbable scaffolds for treatment of coronary artery disease in patients with diabetes mellitus: the midterm follow-up of the prospective ABSORB DM Benelux study.

BACKGROUND: Percutaneous coronary intervention (PCI) in patients with diabetes mellitus (DM) remains challenging even with modern drug-eluting stents (DES) due to high rates of repeat revascularization. Everolimus-eluting bioresorbable scaffolds (EE-BRS) might allow for repeat intervention prolonging the time interval of percutaneous treatment options. METHODS: The ABSORB DM Benelux Study is a dedicated prospective, international study to evaluate the midterm safety and efficacy of EE-BRS in DM patients. All DM patients that received ≥ 1 EE-BRS for any indication were enrolled and prospectively followed. Study endpoints were major adverse cardiac events (MACE): a composite of all-cause death, any myocardial infarction (MI) and ischemic-driven target vessel revascularization (TVR); target lesion failure (TLF): a composite of cardiac death (CD), target vessel MI, and ischemic-driven target lesion revascularization (TLR), as well as definite or probable scaffold thrombosis (ScT). RESULTS: Between April 2015 till March 2017, 150 DM patients and 188 lesions were treated and followed up to 3 years. Device implantation success was 100%. MACE occurred in 15.2% (event rate of 8.8 per 100 PY). TLF was reported in 11.7% (7.0 events per 100 PY). CD, target vessel MI, ischemic-driven TLR occurred in 3.4%, 3.6% and 5.5% respectively, while ScT was observed in 1.4%. There were no occurrences of late or very late ScT. CONCLUSION: EE-BRS treatment in DM patients shows comparable midterm safety and efficacy outcomes when historically compared with modern DES. New-generation EE-BRS might offer an attractive alternative to metallic DES in treatment of fast progressing atherosclerosis population as in DM patients. Trial registration NTR5447. Registered 05 October 2015, retrospectively registered.

Safety and long-term effects of renal denervation: Rationale and design of the Dutch registry.

BACKGROUND: Percutaneous renal denervation (RDN) has recently been introduced as a treatment for therapy-resistant hypertension. Also, it has been suggested that RDN may be beneficial for other conditions characterised by increased sympathetic nerve activity. There are still many uncertainties with regard to efficacy, safety, predictors for success and long-term effects. To answer these important questions, we initiated a Dutch RDN registry aiming to collect data from all RDN procedures performed in the Netherlands. METHODS: The Dutch RDN registry is an ongoing investigator-initiated, prospective, multicentre cohort study. Twenty-six Dutch hospitals agreed to participate in this registry. All patients who undergo RDN, regardless of the clinical indication or device that is used, will be included. Data are currently being collected on eligibility and screening, treatment and follow-up. RESULTS: Procedures have been performed since August 2010. At present, data from 306 patients have been entered into the database. The main indication for RDN was hypertension (n = 302, 99%). Patients had a mean office blood pressure of 177/100 (±29/16) mmHg with a median use of three (range 0-8) blood pressure lowering drugs. Mean 24-hour blood pressure before RDN was 157/93 (±18/13) mmHg. RDN was performed with different devices, with the Simplicity™ catheter currently used most frequently. CONCLUSION: Here we report on the rationale and design of the Dutch RDN registry. Enrolment in this investigator-initiated study is ongoing. We present baseline characteristics of the first 306 participants.

Evaluation of global left ventricular function assessment of non-fluorescent electromechanical endocardial mapping compared with biplane left ventricular contrast angiography.

Background. Little is known about the diagnostic accuracy of global LV function assessment by electromechanical endocardial mapping (EEM). The aim of the present study was to determine the relationship between global left ventricular (LV) function measured by EEM and biplane left ventricular contrast angiography (LVA) after ST-elevation myocardial infarction (STEMI).Methods. Thirty-seven patients underwent LVA and EEM during routine coronary angiography four months after primary percutaneous intervention for STEMI. Global LV function parameters were available from both techniques in all patients. LVA was regarded as reference standard.Results. All procedures were carried out without adverse events. Average age was 55+/-10 years and 84% were male. EEM showed an overestimation of end-diastolic volume (EDV) and end-systolic volume (ESV) of 6.5 ml and 25.5 ml, respectively. Correlation (r) was 0.84 (p<0.001) for EDV and 0.74 (p<0.001) for ESV. Average left ventricular ejection fraction (LVEF) measured by EEM was 17.2% point (+/-11.3% point) lower compared with LVA (r=0.69, p<0.001).Conclusion. Although global functional parameters by EEM correlated well with LVA, the relatively large differences in terms of absolute values for ventricular volumes and LVEF render the two techniques non-interchangeable for global LV-function-data. (Neth Heart J 2010;18:72-77.).

Life-threatening bilateral aorto-ostial coronary artery disease in an octogenarian.

Aorto-ostial disease is difficult to approach percutaneously; therefore, a surgical option may be more desirable. We describe a case of an octogenarian in which the clinical arguments and technical approach have been summarised for a successful percutaneous therapeutic strategy. (Neth Heart J 2009;17:30-2.).

Percutaneous coronary intervention without on site surgical back-up; two-years registry of a large Dutch community hospital.

AIMS: To assess safety and efficacy of off-site percutaneous coronary intervention (PCI) in The Dutch invasive cardiovascular system. METHODS AND RESULTS: Descriptive single centre registry of elective and emergency PCI. Setting is a Dutch community hospital, 40 km north of Amsterdam, with an adherent population of 400,000 people. A Clinical follow up of Major Adverse Cardiac and Cerebral Events (MACCE) at 30 days post PCI is performed. The total number of participants eligible for PCI was 781 of whom 545 were men and 236 women. During a two-year period 781 PCI's were performed of which 298 were emergency and 483 elective. Acute complications occurred in 2.1% of participants. MACCE-free was 86.9% in the group with AMI and 95.8% in the elective group. CONCLUSIONS: Off-site PCI is feasible and safe in The Netherlands on the condition that specific key factors for success are taken into consideration.

Restenosis begets restenosis: implications for stent selection.

BACKGROUND: Identifying the risk for restenosis is of critical importance in the stent selection process of patients undergoing percutaneous coronary intervention (PCI). Therefore, we sought to determine if a history of clinical recurrence (CR) after PCI increases the risk of CR after treatment of a de novo lesion in another coronary artery. METHODS: We retrospectively analysed all 12,763 patients who underwent PCI between 1993 and 2004 and selected patients with two or more interventions in two different native vessels. These patients were divided into two groups: patients without CR, and patients with CR after the first PCI. Clinical recurrence was defined as revascular-isation of the target vessel by either PCI or CABG within one year. RESULTS: A total of 1010 patients with two or more interventions in two different native vessels were identified: 727 patients without and 283 patients with CR after the first PCI. Baseline patient characteristics and conventional risk factors were comparable between the two groups. Patients with a history of CR had a higher risk of CR after a second intervention in a second vessel (OR=3.4, 95% CI=2.3 to 4.9). A total of 112 patients also had a third intervention in a third native vessel: 12 patients with two CR, 30 patients with one CR and 70 patients with no CR after the first two interventions. CR rates in these patients were 50, 17 and 3%, respectively (p<0.001). CONCLUSION: Patients with a history of CR have a markedly increased risk of developing CR after a second or third PCI in a different coronary artery. Therefore, in the decision-making process on whether to use a bare metal stent or drug-eluting stent, the history of CR is a simple and powerful aid. (Neth Heart J 2008;16:376-81.).

Prehospital diagnosis in STEMI patients treated by primary PCI: the key to rapid reperfusion.

BACKGROUND: Primary coronary intervention (PCI) for acute myocardial infarction should be performed as quickly as possible, with a door-toballoon time of less then 90 minutes. However, in daily practice this cannot always be achieved. Prehospital diagnosis of ST-elevation myocardial infarction (STEMI) is of major importance in reducing time to treatment, in particular when patients can be transported directly to a centre with interventional capacities. OBJECTIVES: The aim of the current study was to evaluate the time from prehospital diagnosis of STEMI to balloon inflation and identify factors related to treatment delay in patients directly referred to the catheterisation laboratory of the University Medical Centre of Groningen. METHODS: A cross-sectional descriptive design was used to collect data on patients treated with primary PCI after prehospital diagnosis of STEMI. RESULTS: Median prehospital diagnosis-to-balloon time was 64 minutes for patients directly admitted to the catheterisation laboratory and 75 minutes for patients initially admitted to the coronary care unit. A delay longer than 90 minutes was observed in 18 patients. Higher age was associated with longer delay times (p=0.041). Long delays were not associated with diabetes (p=0.293), time from symptom onset to prehospital diagnosis (p=0.87) or time of day (p=0.09). Initial unavailability of the catheterisation laboratory due to running procedures contributed to longer delay times in ten cases. CONCLUSION: Prehospital diagnosis of STEMI and direct referral to a catheterisation laboratory for primary PCI allows a prehospital diagnosis-toballoon time of less than 90 minutes in 82% of patients. Older patients are at risk of longer delays. (Neth Heart J 2008;16:5-9.).

Mechanisms involved in symptomatic myocardial bridging: Value of sequential testing for endothelial function, flow reserve measurements and dobutamine stress angiography.

BACKGROUND: In patients with extensive myocardial bridging, evaluation of its clinical significance remains a challenge. HYPOTHESIS: Sequential invasive testing is feasible and gives more insight into the pathophysiological mechanism of bridging-related angina. METHODS: Twelve patients with chest pain, proven ischaemia and extensive myocardial bridging were assessed. Myocardial bridging was evaluated at rest, during intracoronary acetylcholine infusion, through coronary flow velocity and flow reserve measurements, and during dobutamine stress. RESULTS: The mean length of the bridging segment was 24.9 mm (QCA; range 8.4-48.0 mm). Acetylcholine infusion caused severe vasospasm in two patients. In these two patients anginal symptoms were related to vasospasm and sequential testing was discontinued. In the remaining ten patients sequential testing was continued. Coronary flow reserve was normal in all patients: 3.3+/-0.6. In six patients reliable quantitative measurements could be performed during dobutamine stress. The mean systolic diameter of the bridging segment was 1.6+/-0.4 at baseline and 1.3+/-0.3 during dobutamine stress (mean of differences 0.38 (95% CI 0.1-0.7)). The difference between the diastolic and systolic diameter in the bridging segment increased from 0.3+/-0.2 mm at baseline to 1.0+/-0.5 mm during dobutamine infusion (mean of differences 0.6 (95% CI 0.3 to 0.9)). CONCLUSION: Sequential testing for bridging is feasible and may disclose endothelial dysfunction or spasm as an underlying mechanism in a minority of patients. Coronary flow reserve was preserved. Dobutamine stress unmasked further lumen reduction and may give further insight into the clinical significance of myocardial bridging in individual patients. (Neth Heart J 2008;16:10-5.).

Discordance between anatomical and functional coronary stenosis severity.

BACKGROUND.: New developments have made 16-slice multidetector computed tomography (MDCT) a promising technique for detecting significant coronary stenoses. At present, there is a paucity of data on the relation between fractional flow reserve (FFR) measurement and MDCT stenosis detection. OBJECTIVE.: The aim of this study was to investigate the relation between the anatomical severity of coronary artery disease detected by MDCT and functional severity measured by fractional flow reserve (FFR). METHODS.: We studied 53 patients (39 men and 14 women, age 62.5+/-8.1 years) with single-vessel disease scheduled for percutaneous coronary intervention (PCI). All patients underwent MDCT scanning one day prior to PCI and FFR was measured before PCI in the target vessel. RESULTS.: MDCT analysis could be performed in 52 of 53 patients (98.1%) and all patients had adequate FFR and quantitative coronary angiography (QCA) measurements. The mean stenosis diameters calculated by MDCT and QCA were 67.0+/-11.6% and 60.8+/-11.6% respectively. No significant relation was found between MDCT and QCA (r=0.22, p=0.12) The mean FFR in all patients was 0.67+/-0.18. A relation of r=-0.46 (p=0.0006) between QCA and FFR was found. In contrast, no relation between MDCT and FFR could be demonstrated (r=-0.09, p=0.50). Furthermore, a high incidence of false-positive and false-negative findings was present in both diagnostic modalities. CONCLUSION.: There is no clear relation between the anatomical and functional severity of coronary artery disease as defined by MDCT and FFR. Therefore, functional assessment of coronary artery disease remains mandatory for clinical decisionmaking. (Neth Heart J 2007;15:5-11.).

Hybrid approach for complex coronary artery and valve disease: a clinical follow-up study.

BACKGROUND: For patients suffering from complex coronary artery disease (CAD) with or without concomitant valve disease, no evidence is available in the current guidelines to propose a predefined treatment regimen. We sought to assess the clinical impact of an unconventional or extended definition of the hybrid approach that combines percutaneous coronary intervention (PCI) and cardiac surgery in subjects suffering from severe solitary CAD or combined with valve disease. METHODS AND RESULTS: Between July 2002 and August 2004, 18 consecutive patients with complex CAD with or without significant valve disease who qualified for a hybrid approach were enrolled in a clinical follow-up study. Four patients eventually did not complete the proposed interventions. One patient refused treatment after inclusion, one patient died before treatment could be undertaken and two patients died after surgery but before PCI. In the other 14 cases combined treatment was technically successful. After a mean follow-up period of 15alpha5 months two patients had died, one due to sudden cardiac death and one of a noncardiac cause. No other major adverse clinical events were reported. A marked increase in quality of life was reported in those alive. CONCLUSION: Hybrid approach had a favourable long-term outcome in patients with complex cardiovascular disease undergoing successful treatment; however, this was observed at the expense of significant periprocedural mortality in these high-risk subjects. Therefore we believe that hybrid approaches may provide an alternative for selected cases. (Neth Heart J 2007;15:329-4.).

[Acute ST-segment elevation also possible in non-coronary disorders]. / Acute ST-segmentelevatie ook mogelijk bij niet-coronaire afwijkingen.

Three patients were referred with symptoms of acute coronary syndrome. The ECG results indicated ST-segment elevation. A 39-year-old man had normal coronary arteries and was eventually diagnosed with pericarditis and myocarditis. A 71-year-old woman had ST-segment elevation caused by mechanical pressure from a chest drain that was inserted for a pneumothorax. A 62-year-old man was admitted to the intensive care unit and was found to have ST-segment elevation related to sepsis and non-significant coronary artery disease. All 3 patients recovered following adequate treatment. Percutaneous coronary intervention is the first choice therapy for ST-segment elevation myocardial infarction (STEMI). However, ST-segment elevation can also occur in patients with non-coronary disorders. Clinicians should be encouraged to scrutinise 'STEMI' as a referral diagnosis and check if there are signs of coronary mimicry, i.e. ECG changes due to a non-coronary underlying cause. The ECG changes should be considered in relation to the clinical data at presentation, rather than interpreted as a single diagnostic finding.

Assessment of coronary artery bypass graft patency by multidetector computed tomography and electron-beam tomography.

This case report describes the use of retrospectively ECG-gated 16-slice multidetector computed tomography (MDCT) and electron-beam tomography (EBT) for assessing bypass graft patency in two patients with recurrent angina after coronary artery bypass graft surgery. The results of each tomographic modality were compared to the findings of traditional coronary angiography. In the first patient MDCT showed occlusion of the left internal mammary artery (LIMA) and saphenous vein graft after the second anastomosis. Coronary angiography confirmed these findings. In the second patient EBT showed patency of the LIMA and saphenous vein graft. After the first anastomosis of the saphenous vein graft, the connected vessel filled poorly. Coronary angiography confirmed both grafts to be patent, and detected an occlusion distal to the first anastomosis. These findings support the evidence that both MDCT and EBT are suitable techniques for establishing bypass graft patency by non-invasive means.

Angioplasty of the left main coronary artery: Mid-term follow-up at University Medical Centre Groningen.

BACKGROUND: Coronary angioplasty is being increasingly performed in complex lesions of the unprotected and protected left main (LM) coronary artery. OBJECTIVES: To assess the impact of patient and operator related clinical variables of success and to evaluate the subsequent mid-term effects of percutaneous treatment of LM coronary stenosis. METHODS: In a tertiary referral, high-volume angioplasty centre a total of 118 consecutive surgical and nonsurgical patients with protected and unprotected LM lesions were treated and evaluated in a retrospective observational study. RESULTS: There were 57 protected and 61 unprotected patients, including 13 patients with an acute myocardial infarction (AMI). Mean age was 67 years (range 33-90). The length of the stenotic segment was 4.8±2.3 mm, mean lumen diameter 1.1±0.6 mm and percentage diameter stenosis 63.6±14.6%. There were seven (5.9%) in-hospital cardiac deaths which presented with AMI and cardiogenic shock. All seven patients had unprotected LM lesions. Average follow-up was eight months (range 1 to 36 months). Major adverse cardiac events (MACE) during follow-up comprised eight (6.8%) cardiac deaths, three (2.5%) myocardial infarctions, eight (6.8%) subjects with coronary bypass surgery and 16 (13.6%) repeated angioplasties. The total event rate (MACE, n=43) at the end of the follow-up period was 36.4%. There were more MACE in the unprotected group than in the protected group (41 vs. 31.6%, p<0.05). CONCLUSION: This study supports prior data on LM angioplasty. LM stenting in AMI, however, showed less favourable in-hospital and late outcome.

Reduction of endothelial dysfunction following VEGF gene therapy.

BACKGROUND/OBJECTIVES: Vascular endothelial growth factor (VEGF) is a potent angiogenic factor. VEGF gene therapy improves perfusion of ischaemic myocardium in experimental models and possibly in patients with end-stage coronary artery disease. In addition to its proliferative and migratory effect on endothelial cells, it also activates and upregulates eNOS. Therefore, we investigated coronary endothelium-dependent vasodilatation in patients before and after VEGF gene therapy. METHODS: The effect of intracoronary acetylcholine infusion on coronary diameter was assessed at baseline and after three months of follow-up in patients with end-stage coronary artery disease treated with VEGF gene and in controls scheduled for elective PTCA (acetylcholine test at diagnostic angiography and before a subsequently scheduled PTCA). RESULTS: Eight out of ten VEGF patients experienced a reduction in anginal symptoms. Angiographic evidence for improved collateral filling was evident in two out of six patients. The vasoconstrictive response to acetylcholine was partly converted into dilatation. In contrast, the acetylcholine response in control patients remained vasoconstrictive. CONCLUSION: VEGF gene therapy has an important beneficial effect on the functional characteristics of the myocardial vascular network. Therefore, this therapy can potentially play an important role in all stages of the atherosclerotic process.

How to target uncertainty in Dutch invasive cardiovascular care.

Current meetings of the Netherlands Society of Cardiology and the Working Group on Intervention Cardiology have shown that new strategic developments in the Dutch healthcare system have created much turbulence and uncertainty amongst members of the organisations. Both on-site and off-site new cardiac centres with and without surgical backup, respectively, are arising or being planned throughout the Netherlands. These strategic adaptations are related to service delivery failure, despite appropriate quality measures. To understand the reasoning behind this uncertainty and how to deal with it, we need to explore its origin and thinking. Its rationale is based on the assumption that each organisation relies on its ability to survive through innovation and transformation. Cardiologists and cardiac surgeons are key players in a large group of stakeholders participating in the chain of cardiovascular care. In addition, the Dutch healthcare system is deeply embedded in a historical sociopolitical environment. This may explain why ongoing uncertainty may beget more uncertainty. What are the consequences for the content of the route forward?

Electrical neuromodulation improves myocardial perfusion and ameliorates refractory angina pectoris in patients with syndrome X: fad or future?

At present, there is no reliable antianginal drug therapy for patients with cardiac syndrome X. Therefore, the effect of electrical neuromodulation on refractory angina pectoris and myocardial perfusion in cardiac syndrome X was assessed. Eight patients (aged 55+/-7 years) with heterogeneous myocardial perfusion and no esophageal abnormalities were included. The subjects were nonresponders to antianginal drug therapy. Angina pectoris attacks and myocardial perfusion dynamics were evaluated by positron emission tomography at baseline and following 4 weeks of (transcutaneous electrical nerve stimulation) TENS. Following TENS there was a reduction of angina pectoris episodes (baseline 20+/-3, TENS 3+/-1; p=0.012), and short acting nitroglycerin intake per week (baseline 10+/-3, TENS 2+/-1; p=0.008). The rate pressure product (mmHg min(-1)) during the cold pressor test (CPT) was reduced during TENS (baseline 12800+/-1200, TENS 11500+/-900; p=0.02). Following TENS, the perfusion reserve ratio between rest and dipyridamole flow increased (baseline 1.59+/-0.15, TENS 1.90+/-0.11 ml min(-1)x 100g; p=0.05). The coronary vascular resistance had a trend towards a reduction (baseline 0.96+/-0.04, TENS 0.85+/-0.06 mmHg min(-1)x 100 g/ml; p=0.06) during CPT. This observation may suggest that neurostimulation improves angina pectoris with a concomitant improvement of myocardial perfusion in cardiac syndrome X.