High-risk Brugada syndrome: factors associated with arrhythmia recurrence and benefits of epicardial ablation in addition to implantable cardioverter defibrillator implantation

AIMS

This study aims to evaluate the prognostic impact of the arrhythmogenic substrate size in symptomatic Brugada syndrome (BrS) as well as to validate the long-term safety and effectiveness of epicardial radiofrequency ablation (RFA) compared with no-RFA group.

METHODS AND RESULTS

In this prospective investigational long-term registry study, 257 selected symptomatic BrS patients with implantable cardioverter defibrillator (ICD) implantation were included. Among them, 206 patients underwent epicardial RFA and were monitored for over 5 years post-ablation (RFA group), while 51 patients received only ICD implantation declining RFA. Primary endpoints included risk factors for ventricular fibrillation (VF) events pre-ablation and freedom from VF events post-ablation. In the RFA group, BrS substrates were identified in the epicardial surface of the right ventricle. During the pre-RFA follow-up period (median 27 months), VF episodes and VF storms were experienced by 53 patients. Independent risk factors included substrate size [hazard ratio (HR), 1.13; 95% confidence interval (CI), 1.08-1.18; P < 0.001], aborted cardiac arrest (HR, 2.98; 95% CI, 1.68-5.28; P < 0.001), and SCN5A variants (HR, 2.22; 95% CI, 1.15-4.27; P = 0.017). In the post-RFA follow-up (median 40 months), the RFA group demonstrated superior outcomes compared with no-RFA (P < 0.001) without major procedure-related complications.

CONCLUSION

Our study underscores the role of BrS substrate extent as a crucial prognostic factor for recurrent VF and validates the safety and efficacy of RFA when compared with a no-RFA group. Our findings highlight the importance of ajmaline in guiding epicardial mapping/ablation in symptomatic BrS patients, laying the groundwork for further exploration of non-invasive methods to guide informed clinical decision-making.

Brugada Syndrome: New Insights From Cardiac Magnetic Resonance and Electroanatomical Imaging

BACKGROUND

Brugada syndrome (BrS) is considered a purely electrical disease with variable electrical substrates. Variable rates of mechanical abnormalities have been also reported. Whether exists a link between electrical and mechanical abnormalities has never been previously explored. This investigational physiopathological study aimed to determine the relationship between the substrate size/location, as exposed by ajmaline provocation, and the severity of mechanical abnormalities, as assessed by cardiac magnetic resonance in patients with BrS.

METHODS

Twenty-four consecutive high-risk patients with BrS (mean age, 38±11 years, 17 males), presenting with malignant syncope and documented polymorphic ventricular tachycardia/ventricular fibrillation, and candidate to implantable cardioverter defibrillator implantation, underwent cardiac magnetic resonance and electroanatomic maps. During each examination, ajmaline test (1 mg/kg over 5 minutes) was performed. Cardiac magnetic resonance findings were compared with 24 age, sex, and body surface area-matched controls. In patients with BrS, the correlation between the electrical substrate extent and right ventricular regional mechanical abnormalities before/after ajmaline challenge was analyzed.

RESULTS

After ajmaline, patients with BrS showed a reduction of right ventricular (RV) ejection fraction (P<0.001), associated with decreased transversal displacement (U, P<0.001) and longitudinal strain (ε, P<0.001) localized at RV outflow tract. In patients with BrS significant preajmaline/postajmaline changes of transversal displacement (ΔU, P<0.001) and longitudinal strain (Δε, P<0.001) were found. In the control group, no mechanical changes were observed after ajmaline. The electrical substrate consistently increased after ajmaline from 1.7±2.8 cm² to 14.2±7.3 cm² (P<0.001), extending from the RV outflow tract to the neighboring segments of the RV anterior wall. Postajmaline RV ejection fraction inversely correlated with postajmaline substrate extent (r=-0.830, P<0.001). In patients with BrS and normal controls, cardiac magnetic resonance detected neither myocardial fibrosis nor RV outflow tract morphological abnormalities.

CONCLUSIONS

BrS is a dynamic RV electromechanical disease, where functional abnormalities correlate with the maximal extent of the substrate size. These findings open new lights on the physiopathology of the disease. Registration: URL: https://clinicaltrial.gov; Unique identifier: NCT03524079.

Brugada syndrome genetics is associated with phenotype severity

Aims 

Brugada syndrome (BrS) is associated with an increased risk of sudden cardiac death due to ventricular tachycardia/fibrillation (VT/VF) in young, otherwise healthy individuals. Despite SCN5A being the most commonly known mutated gene to date, the genotype–phenotype relationship is poorly understood and remains uncertain. This study aimed to elucidate the genotype–phenotype correlation in BrS.

Methods and results

Brugada syndrome probands deemed at high risk of future arrhythmic events underwent genetic testing and phenotype characterization by the means of epicardial arrhythmogenic substrate (AS) mapping, and were divided into two groups according to the presence or absence of SCN5A mutation. Two-hundred probands (160 males, 80%; mean age 42.6 ± 12.2 years) were included in this study. Patients harbouring SCN5A mutations exhibited a spontaneous type 1 pattern and experienced aborted cardiac arrest or spontaneous VT/VF more frequently than the other subjects. SCN5A-positive patients exhibited a larger epicardial AS area, more prolonged electrograms and more frequently observed non-invasive late potentials. The presence of an SCN5A mutation explained >26% of the variation in the epicardial AS area and was the strongest predictor of a large epicardial area.

Conclusion 

In BrS, the genetic background is the main determinant for the extent of the electrophysiological abnormalities. SCN5A mutation carriers exhibit more pronounced epicardial electrical abnormalities and a more aggressive clinical presentation. These results contribute to the understanding of the genetic determinants of the BrS phenotypic expression and provide possible explanations for the varying degrees of disease expression.

Clinical Considerations for a Family with Dilated Cardiomyopathy, Sudden Cardiac Death, and a Novel TTN Frameshift Mutation

Dilated cardiomyopathy (DCM) is the leading indication for heart transplantation. TTN gene truncating mutations account for about 25% of familial DCM cases and for 18% of sporadic DCM cases. The clinical relevance of specific variants in TTN has been difficult to determine because of the sheer size of the protein for which TTN encodes, as well as existing extensive genetic variation. Clinicians should communicate novel clinically-relevant variants and genotype–phenotype associations, so that animal studies evaluating the molecular mechanisms are always conducted with a focus on clinical significance. In the present study, we report for the first time the novel truncating heterozygous variant NM_001256850.1:c.72777_72783del (p.Phe24259Leufs*51) in the TTN gene and its association with DCM in a family with sudden death. This variant occurs in the A-band region of the sarcomere, in a known mutational hotspot of the gene. Truncating titin variants that occur in this region are the most common cause of DCM and have been rarely reported in asymptomatic individuals, differently from other pathogenic TTN gene variants. Further studies are warranted to better understand this particular clinically-relevant variant.

Non-invasive assessment of the arrhythmogenic substrate in Brugada syndrome using signal-averaged electrocardiogram: clinical implications from a prospective clinical trial

AIMS

Brugada syndrome (BrS) represents a major cause of sudden cardiac death in young individuals. The risk stratification to forecast future life-threatening events is still controversial. Non-invasive assessment of late potentials (LPs) has been proposed as a risk stratification tool. However, their nature in BrS is still undetermined. The purpose of this study is to assess the electrophysiological determinants of non-invasive LPs.

METHODS AND RESULTS

Two hundred and fifty consecutive patients with (Group 1, n = 96) and without (Group 2, n = 154) BrS-related symptoms were prospectively enrolled in the registry. Signal-averaged electrocardiogram (SAECG) was performed in all subjects before undergoing epicardial mapping. Group 1 patients exhibited larger arrhythmogenic substrates (AS; 5.8 ± 2.8 vs. 2.6 ± 2.1 cm2, P < 0.001) with more delayed potentials (220.4 ± 46.0 vs. 186.7 ± 42.3 ms, P < 0.001). Late potentials were present in 82/96 (85.4%) Group 1 and in 31/154 (20.1%) Group 2 individuals (P < 0.001). Patients exhibiting LPs had more frequently a spontaneous Type 1 pattern (30.1% vs. 10.9%, P < 0.001), SCN5A mutation (34.5% vs. 21.2%, P = 0.02), and exhibited a larger AS with longer potentials (5.8 ± 2.7 vs. 2.2 ± 1.7 cm2; 231.2 ± 37.3 vs. 213.8 ± 39.0 ms; P < 0.001, respectively). Arrhythmogenic substrate dimension was the strongest predictor of the presence of LPs (odds ratio 1.9; P < 0.001). An AS area of at least 3.5 cm2 identified patients with LPs (area under the curve 0.88, 95% confidence interval 0.843-0.931; P < 0.001) with a sensitivity of 86%, specificity 88%, positive predictive value 85%, and negative predictive value 89%.

CONCLUSION

The results of this study support the role of the epicardial AS as an electrophysiological determinant of non-invasive LPs, which may serve as a tool in the non-invasive assessment of the BrS substrate, as SAECG-LPs could be considered an expression of the abnormal epicardial electrical activity.

ClinicalTrials.gov number (NCT02641431; NCT03106701).

Right ventricular functional changes detected by CMR during ajmaline challenge in patients with Brugada syndrome

Background

3D echocardiography has recently revealed alterations of right ventricular (RV) function in Brugada syndrome (BrS) during ajmaline challenge (AC). Cardiac magnetic resonance (CMR) is the gold standard for functional and anatomical RV assessment. CMR feature-tracking (FT) analysis is able to detect subtle functional changes in the underlying myocardial substrate.

Purpose

To investigate RV functional changes during AC in BrS patients using CMR-FT analysis.

Methods

24 consecutive BrS and 28 matched controls underwent CMR. CMR protocol included paraxial and parasagittal cine bSSFP sequences, acquired before and 2÷5 minutes after ajmaline infusion (1 mg/kg in 5 minutes), to obtain a comprehensive evaluation of the RV free wall. All patients were closely monitored with ECG. Semi-automatic threshold-based quantification of ventricular volumes, function and mass was performed in QMass. CMR-FT analysis of RV function was performed in QStrain. Values of longitudinal strain (LS) and transverse displacement (TD) of the RV wall before and after AC were compared in BrS patients and in the control group.

Results

AC induced Type 1 ECG pattern in all BrS patients and no ECG changes in controls. In BrS patients TD of the RV free wall was significantly reduced (P≤0.003) at peak ajmaline effect; controls reported sub-millimetric TD changes. LS of the RV wall was significantly impaired in BrS patients (P&lt;0.0001) on both b SSFP sequences; LS remained comparable (P=0.62) in controls on the parasagittal sequence; minor but not negligible (P=0.01) LS changes were noticed on the paraxial stack. (Table 1)

Conclusions

In patients with BrS CMR-FT analysis during AC unveils dysfunctional RV wall mechanics in areas generally associated with abnormal electrical activity.

TD and LS in a Brs patient post AC

Funding Acknowledgement

Type of funding source: None

Assessing QT interval in COVID-19 patients:safety of hydroxychloroquine-azithromycin combination regimen

Background

Hydroxychloroquine (HCQ) and azithromycin (AZT) have been proposed for COVID-19 treatment. Data available in the literature reported a potential increased risk of fatal arrhythmias under these therapies. The aim of this study was to assess the effects of these drugs on QT interval and outcome in a COVID-19 population.

Method

A total of 112 consecutive COVID-19 patients were included in this analysis and were divided in 3 groups according to the receiving therapeutic regimens: 19 (17%) patients in Group 1 (no treatment), 40 (36%) in Group 2 (HCQ only), 53 (47%) in Group 3 (HCQ/AZT).

Results

A prolonged QTc interval was found in 61% of patients treated with HCQ alone or in combination with AZT, but only 4 (4%) patients showed a QTc > 500 ms. HCQ/AZT combination determined a greater increase of QTc duration compared to the other two strategies (Group 3 452 ± 26.4 vs Group 2 436.3 ± 28.4 vs Group 1 424.4 ± 24.3 ms, respectively; p < 0.001). Multivariate analysis demonstrated that HCQ/AZT combination (OR 9.02, p = 0.001) and older age (OR 1.04, p = 0.031) were independent predictors of QTc prolongation. The risk increased with age (incremental utility analysis p = 0.02). Twenty patients (18%) died, and no cardiac arrest neither arrhythmic fatalities were documented.

Conclusions

The HCQ/AZT combination therapy causes a significantly increase of QT interval compared to HCQ alone. Older patients under such regimen are at higher risk of experiencing QT prolongation. The use of such drugs may be considered as safe relating to arrhythmic risk in the treatment of COVID-19 patients as no arrhythmic fatalities occurred.

•

Only the use of HCQ in combination with AZT causes a significant increase of QT interval.

•

Older patients are at higher risk of prolonged QT when treated with HCQ with/without AZT.

•

The use of HCQ alone or in combination with AZT might be considered as safe relating to arrhythmic risk in the treatment of COVID-19 patients.

Novel CineECG Derived From Standard 12-Lead ECG Enables Right Ventricle Outflow Tract Localization of Electrical Substrate in Patients With Brugada Syndrome

Background:

In Brugada syndrome (BrS), diagnosed in presence of a spontaneous or ajmaline-induced type-1 pattern, ventricular arrhythmias originate from the right ventricle outflow tract (RVOT). We developed a novel CineECG method, obtained by inverse electrocardiogram (ECG) from standard 12-lead ECG, to localize the electrical activity pathway in patients with BrS.

Methods:

The CineECG enabled the temporospatial localization of the ECG waveforms, deriving the mean temporospatial isochrone from standard 12-lead ECG. The study sample included (1) 15 patients with spontaneous type-1 Brugada pattern, and (2) 18 patients with ajmaline-induced BrS (at baseline and after ajmaline), in whom epicardial potential duration maps were available; (3) 17 type-3 BrS pattern patients not showing type-1 BrS pattern after ajmaline (ajmaline-negative); (4) 47 normal subjects; (5) 18 patients with right bundle branch block (RBBB). According to CineECG algorithm, each ECG was classified as Normal, Brugada, RBBB, or Undetermined.

Results:

In patients with spontaneous or ajmaline-induced BrS, CineECG localized the terminal mean temporospatial isochrone forces in the RVOT, congruent with the arrhythmogenic substrate location detected by epicardial potential duration maps. The RVOT location was never observed in normal, RBBB, or ajmaline-negative patients. In most patients with ajmaline-induced BrS (78%), the RVOT location was already evident at baseline. The CineECG classified all normal subjects and ajmaline-negative patients at baseline as Normal or Undetermined, all patients with RBBB as RBBB, whereas all patients with spontaneous and ajmaline-induced BrS as Brugada. Compared with standard 12-lead ECG, CineECG at baseline had a 100% positive predictive value and 81% negative predictive value in predicting ajmaline test results.

Conclusions:

In patients with spontaneous and ajmaline-induced BrS, the CineECG localized the late QRS activity in the RVOT, a phenomenon never observed in normal, RBBB, or ajmaline-negative patients. The possibility to identify the RVOT as the location of the arrhythmogenic substrate by the noninvasive CineECG, based on the standard 12-lead ECG, opens new prospective for diagnosing patients with BrS.

New electromechanical substrate abnormalities in high-risk patients with Brugada syndrome

BACKGROUND

The relationship between the typical electrocardiographic pattern and electromechanical abnormalities has never been systematically explored in Brugada syndrome (BrS).

OBJECTIVES

The aims of this study were to characterize the electromechanical substrate in patients with BrS and to evaluate the relationship between electrical and mechanical abnormalities.

METHODS

We enrolled 50 consecutive high-risk patients with BrS (mean age 42 ± 7.2 years), with implantable cardioverter-defibrillator implantation for primary or secondary prevention of ventricular tachyarrhythmias (ventricular tachycardia/ventricular fibrillation [VT/VF]), undergoing substrate mapping and ablation. Patients underwent 3-dimensional (3D) echocardiography with 3D wall motion/deformation quantification and electroanatomic mapping before and after ajmaline administration (1 mg/kg in 5 minutes); 3D mechanical changes were compared with 50 age- and sex-matched controls. The effect of substrate ablation on electromechanical abnormalities was also assessed.

RESULTS

In all patients, ajmaline administration induced Brugada type 1 pattern, with a significant increase in the electrical substrate (P < .001), particularly in patients with previous spontaneous VT/VF (P = .007). Induction of Brugada pattern was associated with lowering of right ventricular (RV) ejection fraction (P < .001) and worsening of 3D RV mechanical function (P < .001), particularly in the anterior free wall of the RV outflow tract, without changes in controls. RV electrical and mechanical abnormalities were highly correlated (r = 0.728, P < .001). By multivariate analysis, only the area of RV dysfunction was an independent predictor of spontaneous VT/VF (odds ratio 1.480; 95% confidence interval 1.159-1.889; P = .002). Substrate ablation abolished both BrS-electrocardiographic pattern and mechanical abnormalities, despite ajmaline rechallenge.

CONCLUSION

BrS is an electromechanical disease affecting the RV. The typical BrS pattern reflects an extensive RV arrhythmic substrate, driving consistent RV mechanical abnormalities. Substrate ablation abolished both Brugada pattern and mechanical abnormalities.

Assessing the Malignant Ventricular Arrhythmic Substrate in Patients With Brugada Syndrome

BACKGROUND

Guidelines recommend the use of implanted cardioverter-defibrillators in patients with Brugada syndrome and induced ventricular tachyarrhythmias, but there is no evidence supporting it.

OBJECTIVES

This prospective registry study was designed to explore clinical and electrophysiological predictors of malignant ventricular tachyarrhythmia inducibility in Brugada syndrome.

METHODS

A total of 191 consecutive selected patients with (group 1; n = 88) and without (group 2; n = 103) Brugada syndrome-related symptoms were prospectively enrolled in the registry. Patients underwent electrophysiological study and substrate mapping or ablation before and after ajmaline testing (1 mg/kg/5 min).

RESULTS

Overall, before ajmaline testing, 53.4% of patients had ventricular tachyarrhythmia inducibility, which was more frequent in group 1 (65.9%) than in group 2 (42.7%; p < 0.001). Regardless of clinical presentation, larger substrates with more fragmented long-duration ventricular potentials were found in patients with inducible arrhythmias than in patients without inducible arrhythmias (p < 0.001). One extrastimulus was used in more extensive substrates (median 13 cm²; p < 0.001), and ventricular fibrillation was the more frequently induced rhythm (p < 0.001). After ajmaline, patients without arrhythmia inducibility had arrhythmia inducibility without a difference in substrate characteristics between the 2 groups. The substrate size was the only independent predictor of inducibility (odds ratio: 4.51; 95% confidence interval: 2.51 to 8.09; p < 0.001). A substrate size of 4 cm² best identified patients with inducible arrhythmias (area under the curve: 0.98; p < 0.001). Substrate ablation prevented ventricular tachyarrhythmia reinducibility.

CONCLUSIONS

In Brugada syndrome dynamic substrate variability represents the pathophysiological basis of lethal ventricular tachyarrhythmias. Substrate size is independently associated with arrhythmia inducibility, and its determination after ajmaline identifies high-risk patients missed by clinical criteria. Substrate ablation is associated with electrocardiogram normalization and not arrhythmia reinducibility. (Epicardial Ablation in Brugada Syndrome [BRUGADA_I]; NCT02641431; Epicardial Ablation in Brugada Syndrome: An Extension Study of 200 BrS Patients; NCT03106701).

Novel SCN5A Frameshift Mutation in Brugada Syndrome Associated With Complex Arrhythmic Phenotype

In this case report, we characterize a novel inherited frameshift mutation c.4700_4701del (p.Phe1567Cysfs^*221) in a single copy of the SCN5A gene and its association with Brugada syndrome (BrS). The proband experienced a life-threatening ventricular arrhythmia successfully treated with DC-shock and he also suffered from supraventricular tachycardia. Ajmaline test confirmed the BrS diagnosis. No other mutation nor low frequency variants in the other 23 analyzed genes were detected. The same mutation was found in the father and sister, who were both diagnosed with BrS. We hypothesize that this mutation could be responsible for BrS and potentially linked to supraventricular tachycardias. Further studies are needed to confirm this observation and to assess the clinical relevance of this mutation, in terms of risk-stratification.

SCN5A Nonsense Mutation and NF1 Frameshift Mutation in a Family With Brugada Syndrome and Neurofibromatosis

In this case series, we report for the first time a family in which the inherited nonsense mutation [c. 3946C > T (p.Arg1316*)] in the SCN5A gene segregates in association with Brugada syndrome (BrS). Moreover, we also report, for the first time, the frameshift mutation [c.7686delG (p.Ile2563fsX40)] in the NF1 gene, as well as its association with type 1 neurofibromatosis (NF1), characterized by pigmentary lesions (café au lait spots, Lisch nodules, freckling) and cutaneous neurofibromas. Both of these mutations and associated phenotypes were discovered in the same family. This genetic association may identify a subset of patients at higher risk of sudden cardiac death who require the appropriate electrophysiological evaluation. This case series highlights the importance of genetic testing not only to molecularly confirm the pathology but also to identify asymptomatic family members who need clinical examinations and preventive interventions, as well as to advise about the possibility of avoiding recurrence risk with medically assisted reproduction.

P210Long- term outcome of primary mitral valve prolapse: results from a population of 250 patients referred to a tertiary cardiovascular center

Background

Outcome of Mitral Valve Prolapse (MVP) was controversial for long time. Many studies reported great differences in the incidence of cardiovascular events due, above all, to heterogeneous and small studied populations. Most of theme were also published to late '80 of the last century till early '00.

Purpose

To make a contemporary survey on the incidence of cardiovascular events in a selected population of patients affected by primary MVP referred to a tertiary cardiovascular center for the medical and surgical care of valvular heart disease.

Methods

We reviewed our MVP database; patients with at least 2 cardiologic evaluations inclusive of echocardiographic examination and at least 6 months follow up were enrolled. A total of 250 patients (126 F) were selected. Their mean age was 52.1 years (ranging from 13 to 88 yo). The average follow-up time was 100 months (8,33 yrs).

Results

At the first medical and echocardiographic examination 8 patients (3,2%) had no mitral regurgitation (MR), 104 (41.6%) have a trace/mild MR, 93 (37,2%) a moderate MR and 46 (18,4%) a severe MR. They were widely asymptomatic (NYHA I 205-82%, NYHA II 44-17.60%, NYHA III 1- 0.40%). Most of theme presented a bileaflet (140-55.8%) or a posterior MVP (94 - 37.6%); an isolated anterior MVP was rare (16 - 6,4%). Flail leaflet was present in 8 (3,2%) and 25 (10%) had a chordal rupture. Respectively 165 (65,6%) and 115 (46,1%) patients had thick and redundant leaflets. Mean antero-posterior mitral annulus diameter was 37 mm. During the follow up 7 patients died of non-cardiac cause and 5 (2%) of suspected cardiac cause (2 because of acute coronary syndrome and 3 died suddenly). MR progresses in 43 (17,2%) patients and finally we observed 81 (32,4%) moderate/severe and severe MR. 12 new chordal rupture occurred during the follow up in most cases concerning mitral chordae linked to posterior mitral leaflet (10 cases-83,3%). The worsening of MR provoked an evolution of the clinical condition of 48 patients (19.2%) which developed Dyspnea On Excertion (DOE) with 42 new NYHA II and 6 new NYHA III. At the end of the follow up the amount of patients symptomatic for DOE was 93 (37.2% vs 18% at the initial evaluation). A total of 45 patients (18%) underwent mitral valve surgery. 40 needed in-hospital treatment in most cases due to the development of atrial fibrillation (19 -7.6%) or heart failure ( 8- 3,2%). Endocarditis occurred in 4 patients (1.6%) and cerebrovascular accidents/cardioembolic event in 6 (2.4%). The overall cardiovascular event rate was 4,33/100 patients-year, significantly higher than reported in community based studies.

Conclusions

The prognosis of a MVP population referred to a tertiary cardiovascular center is not benign. The most frequent complications are progression of MR and MV surgery. Sudden death is also more frequent than in general population. More studies are needed to identify what patients with MVP are at risk for it.

Dual antiplatelet therapy tailored on platelet function test after coronary stent implantation: a real-world experience

Patients' response to dual antiplatelet therapy (DAPT) is subject to variations and its monitoring allows to individualize this therapy. In this study, we evaluated if a strategy of tailored DAPT after platelet function testing could reduce high on-treatment platelet reactivity (HPR) and improve outcome of patients treated with stent implantation. In 257 patients undergoing percutaneous angioplasty, platelet function was measured by light transmittance aggregometry (LTA) using 10 µM/L adenosine-diphosphate (ADP) and 1 mM arachidonic acid (AA) as agonists. Patients with HPR by ADP (≥70%) were switched to double-dose clopidogrel, ticlopidine, prasugrel or ticagrelor; in patients with HPR by AA (≥20%) acetylsalicylic acid dose was increased if not contraindicated. Platelet function analysis was repeated 48 hours after therapy variation. At 20-month follow-up major adverse cardiovascular events (MACE) and bleedings were assessed. HPR was detected in 97/257 (37.7%) patients: 69/257 (26.8%) had HPR by ADP and 71/257 (27.6%) had HPR by AA. In patients with HPR by ADP or by AA, tailored DAPT determined a significant reduction in residual platelet reactivity. No significant difference in MACE or bleeding occurrence was documented in HPR patients treated with tailored DAPT vs. those without HPR. HPR patients treated with tailored DAPT had significant lower follow-up MACE and deaths vs. 139 HPR patients not switched, even after propensity score analysis. These results suggest that a DAPT tailored on platelet testing can improve antiplatelet response in HPR patients, possibly reducing their thrombotic events to a level similar to non-HPR patients, without increasing the risk of bleeding.