Fast polynomial multiplication using matrix multiplication accelerators with applications to NTRU on Apple M1/M3 SoCs

Efficient polynomial multiplication routines are critical to the performance of lattice-based post-quantum cryptography (PQC). As PQC standards only recently started to emerge, CPUs still lack specialized instructions to accelerate such routines. Meanwhile, deep learning has grown immeasurably in importance. Its workloads call for teraflops-level of processing power for linear algebra operations, mainly matrix multiplication. Computer architects have responded by introducing ISA extensions, coprocessors and special-purpose cores to accelerate such operations. In particular, Apple ships an undocumented matrix-multiplication coprocessor, AMX, in hundreds of millions of mobile phones, tablets and personal computers. Our work repurposes AMX to implement polynomial multiplication and applies it to the NTRU cryptosystem, setting new speed records on the Apple M1 and M3 systems-on-chip (SoCs)

Ablaçao por Cateter de Taquicardias Ventriculares em Pacientes sem Cardiopatia Estrutural

As taquicardias ventriculares idiopáticas ocorrem em pacientes com coraçao estruturalmente normal e podem se originar nos dois ventrículos ou em estruturas vizinhas. Essas arritmias sao classificadas usualmente conforme o seu local de origem, mecanismo eletrofisiológico e resposta à drogas, apresentando bom prognóstico na maioria dos casos. A ablaçao por cateter é uma opçao terapêutica importante, geralmente empregada após o manejo clínico inicial, sendo o tratamento guiado principalmente pelos sintomas. As técnicas de ablaçao tradicionais permitem tratar com sucesso a maioria das TV idiopáticas, com o auxílio de sistemas de mapeamento eletroanatômico em alguns casos

Ablaçao por Cateter de Taquicardias Ventriculares em Pacientes sem Cardiopatia Estrutural

As taquicardias ventriculares idiopáticas ocorrem em pacientes com coraçao estruturalmente normal e podem se originar nos dois ventrículos ou em estruturas vizinhas. Essas arritmias sao classificadas usualmente conforme o seu local de origem, mecanismo eletrofisiológico e resposta à drogas, apresentando bom prognóstico na maioria dos casos. A ablaçao por cateter é uma opçao terapêutica importante, geralmente empregada após o manejo clínico inicial, sendo o tratamento guiado principalmente pelos sintomas. As técnicas de ablaçao tradicionais permitem tratar com sucesso a maioria das TV idiopáticas, com o auxílio de sistemas de mapeamento eletroanatômico em alguns casos

Incidence of Esophageal Thermal Injury Using a Safety Protocol During Atrial Fibrillation Ablation

Objective: Catheter ablation has been a common procedure used for the management of atrial fibrillation (AF). Atrioesophagel fistula (AEF) is one of the most feared complications of AF ablation. Although it is a rare complication, severe esophageal thermal injury must be avoided. It is important to describe a safe method of preventing esophageal injuries without increasing AF recurrence. Methods: A retrospective cohort study of consecutive patients who underwent radiofrequency AF catheter ablation during 1 year-period wa conducted. One hundred and four patients were enrolled divided in two groups: one with a maximum recorded esophageal temperature (ET) < 38 °C and other with a maximum recorded ET ≥ 38 °C. The primary endpoint was detection of endoscopic esophageal lesions after AF ablation and the secondary endpoint was AF recurrence according to the maximum ET reached during the procedure. Results: The maximum ET was on average 37.3 ± 1.0 °C. Only 4 (3.8%) patients had esophageal lesion diagnosed by upper gastrointestinal endoscopy. There were no cases of esophageal perforation. The AF recurrence rate was 9.6% during the follow-up (10 patients, 3 from the ET max < 38 °C group and 7 from the ET max ≥ 38 °C group; p = 0.181). The maximum ET was not associated with AF recurrence after catheter ablation (OR = 1.65, 95% CI = 0.84-3.24, p = 0.14). Conclusions: A low incidence of esophageal injury after AF ablation with the use of a specific esophageal protection protocol was found. There was no esophageal perforation. The AF recurrence rate was similar to that described in the literature

Incidence of Esophageal Thermal Injury Using a Safety Protocol During Atrial Fibrillation Ablation

Objective: Catheter ablation has been a common procedure used for the management of atrial fibrillation (AF). Atrioesophagel fistula (AEF) is one of the most feared complications of AF ablation. Although it is a rare complication, severe esophageal thermal injury must be avoided. It is important to describe a safe method of preventing esophageal injuries without increasing AF recurrence. Methods: A retrospective cohort study of consecutive patients who underwent radiofrequency AF catheter ablation during 1 year-period wa conducted. One hundred and four patients were enrolled divided in two groups: one with a maximum recorded esophageal temperature (ET) < 38 °C and other with a maximum recorded ET ≥ 38 °C. The primary endpoint was detection of endoscopic esophageal lesions after AF ablation and the secondary endpoint was AF recurrence according to the maximum ET reached during the procedure. Results: The maximum ET was on average 37.3 ± 1.0 °C. Only 4 (3.8%) patients had esophageal lesion diagnosed by upper gastrointestinal endoscopy. There were no cases of esophageal perforation. The AF recurrence rate was 9.6% during the follow-up (10 patients, 3 from the ET max < 38 °C group and 7 from the ET max ≥ 38 °C group; p = 0.181). The maximum ET was not associated with AF recurrence after catheter ablation (OR = 1.65, 95% CI = 0.84-3.24, p = 0.14). Conclusions: A low incidence of esophageal injury after AF ablation with the use of a specific esophageal protection protocol was found. There was no esophageal perforation. The AF recurrence rate was similar to that described in the literature

Avaliaçao da funçao renal após a terapia de ressincronizaçao cardíaca

OBJETIVO: A insuficiência renal crônica (IRC), presente em metade dos portadores de insuficiência cardíaca (IC), está associada ao aumento de mortalidade nessa populaçao. A terapia de ressincronizaçao cardíaca (TRC), que traz benefícios aos pacientes com IC, também pode melhorar a IRC. O objetivo deste estudo foi avaliar a funçao renal após a TRC. MÉTODO: Estudo de coorte, retrospectivo, de pacientes que se submeteram a TRC de julho de 2004 a maio de 2010, para analisar a taxa de filtraçao glomerular (TFG) pré-operatória e seis meses após a TRC. RESULTADOS: Foram incluídos 67 pacientes, com idade média de 68 anos, 70% dos quais eram renais crônicos nao dialíticos. A média da creatinina prévia à TRC foi de 1,47 mg/dl e seu valor após a TRC foi de 1,35 mg/dl (p2) e após a TRC (54,3 ml/min/1,73 m2), com valor de p=0,144. Entretanto, quando analisadas as TFG nos subgrupos, verificou-se melhora importante da funçao renal nos pacientes que apresentavam TFG menor antes da TRC. Naqueles em estágio 3 da funçao renal, observou-se acréscimo de 7,2 ml/min/1,73 m2 após a TRC; o que representa uma melhora da funçao renal de 15,45%. Nos que estavam em estágio 4, o ganho foi de 11,7 ml/min/1,73 m2 após a TRC, um incremento de 48,34%. CONCLUSAO: A TRC proporcionou melhora da TFG nos pacientes com IRC moderada a severa, porém nao apresentou impacto na funçao renal dos pacientes com TFG inicial >60 ml/min/1,73 m2

Avaliaçao da funçao renal após a terapia de ressincronizaçao cardíaca

OBJETIVO: A insuficiência renal crônica (IRC), presente em metade dos portadores de insuficiência cardíaca (IC), está associada ao aumento de mortalidade nessa populaçao. A terapia de ressincronizaçao cardíaca (TRC), que traz benefícios aos pacientes com IC, também pode melhorar a IRC. O objetivo deste estudo foi avaliar a funçao renal após a TRC. MÉTODO: Estudo de coorte, retrospectivo, de pacientes que se submeteram a TRC de julho de 2004 a maio de 2010, para analisar a taxa de filtraçao glomerular (TFG) pré-operatória e seis meses após a TRC. RESULTADOS: Foram incluídos 67 pacientes, com idade média de 68 anos, 70% dos quais eram renais crônicos nao dialíticos. A média da creatinina prévia à TRC foi de 1,47 mg/dl e seu valor após a TRC foi de 1,35 mg/dl (p2) e após a TRC (54,3 ml/min/1,73 m2), com valor de p=0,144. Entretanto, quando analisadas as TFG nos subgrupos, verificou-se melhora importante da funçao renal nos pacientes que apresentavam TFG menor antes da TRC. Naqueles em estágio 3 da funçao renal, observou-se acréscimo de 7,2 ml/min/1,73 m2 após a TRC; o que representa uma melhora da funçao renal de 15,45%. Nos que estavam em estágio 4, o ganho foi de 11,7 ml/min/1,73 m2 após a TRC, um incremento de 48,34%. CONCLUSAO: A TRC proporcionou melhora da TFG nos pacientes com IRC moderada a severa, porém nao apresentou impacto na funçao renal dos pacientes com TFG inicial >60 ml/min/1,73 m2

Advances in Physiological Cardiac Stimulation

Advances in cardiac stimulation demonstrate that bradyarrhythmia treatments go beyond heart rate control. The concern with the ventricular stimulation site and, consequently, with the maintenance of intraventricular synchrony has become routine in most services. Techniques of physiological cardiac stimulation, such as stimulation of the bundle of His and the left branch, have been improved. Despite the indisputable benefits of these therapeutic modalities, there are technical difficulties that limit systematic use. In this sense, to make physiological cardiac stimulation more practical and reproducible, the concept of parahissian stimulation was expanded and studied. The technique, simpler and reproducible, contemplates a conventional approach of the right ventricle. The big difference is the use of QRS spatial variance analysis technology (Synchromax®, Exo S.A., Argentina) to confirm the maintenance of ventricular synchrony according to the implanted site

Advances in Physiological Cardiac Stimulation

Advances in cardiac stimulation demonstrate that bradyarrhythmia treatments go beyond heart rate control. The concern with the ventricular stimulation site and, consequently, with the maintenance of intraventricular synchrony has become routine in most services. Techniques of physiological cardiac stimulation, such as stimulation of the bundle of His and the left branch, have been improved. Despite the indisputable benefits of these therapeutic modalities, there are technical difficulties that limit systematic use. In this sense, to make physiological cardiac stimulation more practical and reproducible, the concept of parahissian stimulation was expanded and studied. The technique, simpler and reproducible, contemplates a conventional approach of the right ventricle. The big difference is the use of QRS spatial variance analysis technology (Synchromax®, Exo S.A., Argentina) to confirm the maintenance of ventricular synchrony according to the implanted site