Karim D Mahmoud

Dr. Karim D Mahmoud


Research Focus & Metrics

Academic Career Length

16Years (2011-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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10 January 2017 in Circulation
Verified
Journal Article
Closed access
SJSanjit S. Jolly
Sanjit S. Jolly
SJStefan James
Stefan James
VDVladimír Džavík
Vladimír Džavík
JCJohn A. Cairns
John A. Cairns
KMKarim D Mahmoud
Karim D Mahmoud
OFOle Frøbert
Ole Frøbert
Background: Thrombus aspiration during percutaneous coronary intervention (PCI) for the treatment of ST-segment–elevation myocardial infarction (STEMI) has been widely used; however, recent trials have questioned its value and safety. In this meta-analysis, we, the trial investigators, aimed to pool the individual patient data from these trials to determine the benefits and risks of thrombus aspiration during PCI in patients with ST-segment–elevation myocardial infarction. Methods: Included were large (n≥1000), randomized, controlled trials comparing manual thrombectomy and PCI alone in patients with ST-segment–elevation myocardial infarction. Individual patient data were provided by the leadership of each trial. The prespecified primary efficacy outcome was cardiovascular mortality within 30 days, and the primary safety outcome was stroke or transient ischemic attack within 30 days. Results: The 3 eligible randomized trials (TAPAS [Thrombus Aspiration During Percutaneous Coronary Intervention in Acute Myocardial Infarction], TASTE [Thrombus Aspiration in ST-Elevation Myocardial Infarction in Scandinavia], and TOTAL [Trial of Routine Aspiration Thrombectomy With PCI Versus PCI Alone in Patients With STEMI]) enrolled 19 047 patients, of whom 18 306 underwent PCI and were included in the primary analysis. Cardiovascular death at 30 days occurred in 221 of 9155 patients (2.4%) randomized to thrombus aspiration and 262 of 9151 (2.9%) randomized to PCI alone (hazard ratio, 0.84; 95% confidence interval, 0.70–1.01; P =0.06). Stroke or transient ischemic attack occurred in 66 (0.8%) randomized to thrombus aspiration and 46 (0.5%) randomized to PCI alone (odds ratio, 1.43; 95% confidence interval, 0.98–2.10; P =0.06). There were no significant differences in recurrent myocardial infarction, stent thrombosis, heart failure, or target vessel revascularization. In the subgroup with high thrombus burden (TIMI [Thrombolysis in Myocardial Infarction] thrombus grade ≥3), thrombus aspiration was associated with fewer cardiovascular deaths (170 [2.5%] versus 205 [3.1%]; hazard ratio, 0.80; 95% confidence interval, 0.65–0.98; P =0.03) and with more strokes or transient ischemic attacks (55 [0.9%] versus 34 [0.5%]; odds ratio, 1.56; 95% confidence interval, 1.02–2.42, P =0.04). However, the interaction P values were 0.32 and 0.34, respectively. Conclusions: Routine thrombus aspiration during PCI for ST-segment–elevation myocardial infarction did not improve clinical outcomes. In the high thrombus burden group, the trends toward reduced cardiovascular death and increased stroke or transient ischemic attack provide a rationale for future trials of improved thrombus aspiration technologies in this high-risk subgroup. Clinical Trial Registration: URLs: http://www.ClinicalTrials.gov http://www.crd.york.ac.uk/prospero/ . Unique identifiers: NCT02552407 and CRD42015025936.

1 August 2011 in JACC
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Journal Article
Closed access
PVPieter J. Vlaar
Pieter J. Vlaar
KMKarim D Mahmoud
Karim D Mahmoud
DHDavid R. Holmes
David R. Holmes
GVGert van Valkenhoef
Gert van Valkenhoef
HHHans L. Hillege
Hans L. Hillege
BSBart J.G.L. de Smet
Bart J.G.L. de Smet

6 March 2018 in Circulation
Verified
Journal Article
Closed access
COConstantinos O’mahony
Constantinos O’mahony
FJFatima Jichi
Fatima Jichi
SOSteve R. Ommen
Steve R. Ommen
ICImke Christiaans
Imke Christiaans
EAEloisa Arbustini
Eloisa Arbustini
Perry ElliottPerry Elliott
Perry Elliott
Background: Identification of people with hypertrophic cardiomyopathy (HCM) who are at risk of sudden cardiac death (SCD) and require a prophylactic implantable cardioverter defibrillator is challenging. In 2014, the European Society of Cardiology proposed a new risk stratification method based on a risk prediction model (HCM Risk-SCD) that estimates the 5-year risk of SCD. The aim was to externally validate the 2014 European Society of Cardiology recommendations in a geographically diverse cohort of patients recruited from the United States, Europe, the Middle East, and Asia. Methods: This was an observational, retrospective, longitudinal cohort study. Results: The cohort consisted of 3703 patients. Seventy three (2%) patients reached the SCD end point within 5 years of follow-up (5-year incidence, 2.4% [95% confidence interval {CI}, 1.9–3.0]). The validation study revealed a calibration slope of 1.02 (95% CI, 0.93–1.12), C-index of 0.70 (95% CI, 0.68–0.72), and D-statistic of 1.17 (95% CI, 1.05–1.29). In a complete case analysis (n= 2147; 44 SCD end points at 5 years), patients with a predicted 5-year risk of <4% (n=1524; 71%) had an observed 5-year SCD incidence of 1.4% (95% CI, 0.8–2.2); patients with a predicted risk of ≥6% (n=297; 14%) had an observed SCD incidence of 8.9% (95% CI, 5.96–13.1) at 5 years. For every 13 (297/23) implantable cardioverter defibrillator implantations in patients with an estimated 5-year SCD risk ≥6%, 1 patient can potentially be saved from SCD. Conclusions: This study confirms that the HCM Risk-SCD model provides accurate prognostic information that can be used to target implantable cardioverter defibrillator therapy in patients at the highest risk of SCD.

1 March 2016 in JACC
Verified
Journal Article
Closed access
KMKarim D Mahmoud
Karim D Mahmoud
SSSaurabh Sanon
Saurabh Sanon
EHElizabeth B. Habermann
Elizabeth B. Habermann
RLRyan J. Lennon
Ryan J. Lennon
KTKristine M. Thomsen
Kristine M. Thomsen
DHDavid R. Holmes
David R. Holmes

10 March 2016 in Nature Reviews Cardiology
Verified
Journal Article
Closed access
KMKarim D Mahmoud
Karim D Mahmoud
FZFelix Zijlstra
Felix Zijlstra

11 February 2013 in European Heart Journal: Acute Cardiovascular Care
Verified
Journal Article
Closed access
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KMKarim D Mahmoud
Karim D Mahmoud
YGYoulan L Gu
Youlan L Gu
MNMaarten W Nijsten
Maarten W Nijsten
RVRonald de Vos
Ronald de Vos
WNWybe Nieuwland
Wybe Nieuwland
BSBart Jgl de Smet
Bart Jgl de Smet
Background: For patients with ST-elevation myocardial infarction (STEMI), guidelines recommend prehospital triage and direct referral to a percutaneous coronary intervention (PCI)-capable centre in order to minimize ischemic time. However, few have studied failed prehospital diagnosis. We assessed the incidence, predictors, and clinical impact of interhospital transfer for primary PCI after initial referral to a non-PCI-capable centre due to a failed prehospital STEMI diagnosis. Methods: We studied 846 consecutive STEMI patients undergoing primary PCI between January 2008 and January 2010. Results: We found that 609 patients (72%) were directly admitted through prehospital triage and 127 patients (15%) required interhospital transfer after failed prehospital diagnosis. Median first medical contact to treatment time was 88 min in the prehospital diagnosis group and 155 min in the interhospital transfer group (p<0.001). In the interhospital transfer group, the first available electrocardiogram was diagnostic for STEMI in 77% of cases. Predictors of interhospital transfer were female gender, diabetes, prior myocardial infarction, and greater event location to PCI-capable centre distance. Interhospital transfer independently accounted for a 47% increase in ischemic time (95% CI 33 to 63%; p<0.001). One-year mortality was higher in the interhospital transfer group (10 vs. 5.3%; p=0.030). Conclusions: Despite an often-diagnostic electrocardiogram, interhospital transfer after failed prehospital diagnosis occurred in 15% of STEMI patients undergoing primary PCI. Interhospital transfer was a major predictor of ischemic time and 1-year mortality was significantly higher. Continuing efforts to optimize prehospital triage are warranted, especially among patients at higher risk of failed prehospital diagnosis.