Contemporary Yield of 24-hour Holter Monitoring: Role of Inter-Atrial Block Recognition.

BACKGROUND: The diagnostic yield of 24-hour ECG Holter monitoring (24H) is currently overcome by alternative ECG monitoring techniquesand it needs to be optimized. The recognition of inter-atrial block (IAB) has emerged as a reliable indicator of patients at risk of atrial fibrillation relapses, and its role enhancing the yield of 24H is yet to be determined. We hypothesized that a presumably low yield of 24H may be ameliorated by means of incorporating the assessment for IAB. METHODS: We retrospectively analyzed 1017 consecutive 24H registers performed in a Multidisciplinary Integrated Health Care Institution, in which a restrictive definition of diagnostic 24H findings was used. A univariate and multivariate regression analysis served to determine the variables associated with a higher 24H's yield, including the requesting medical specialty, type of indication and a number of clinical, echocardiographic and ECG variables, including IAB. RESULTS: The mean age of our population was 62 ± 17 years (55% males). The majority of 24H were indicated from the Cardiology department (48%). The overall yield was 12.8%, higher for the assessment of the integrity of the electrical conduction system (26.1%) and poorer for the assessment of syncope (3.2%) and cryptogenic stroke (4.6%). The variables associated with higher diagnostic performance were indication from Cardiology (p < 0.001), IAB (p = 0.004), structural heart disease (p = 0.008) and chronic renal failure (p = 0.009). Patients ≤ 50 years old only retrieved a 7% yield. In the multivariate analysis, indication from Cardiology and IAB remained significant predictors of higher 24H's yield. In a secondary analysis including echocardiographic data, only identification of IAB remained statistically significant. CONCLUSIONS: The recognition of IAB and the type of indication are major determinants of a higher 24H's diagnostic yield and may help to optimize the selection of candidates.

[Neointimal tissue proliferation after coronary stent implantation without predilatation]. / Proliferación neointimal después de la implantación coronaria de stent sin predilatación.

INTRODUCTION AND OBJECTIVES: Intravascular ultrasound (IVUS) studies in conventional stent angioplasty with predilatation have demonstrated that late luminal narrowing is caused by neointimal proliferation. In the present study, we analyzed the degree and distribution of in-stent neointimal proliferation after direct stent implantation and aimed to identify variables that predict a proliferative response. MATERIAL AND METHOD: We studied 45 patients who underwent successful stent implantation without predilatation and 23 patients with similar clinical and angiographic characteristics who underwent conventional stent angioplasty with predilatation. IVUS imaging was performed at 7.85+/-2.81 months. The cross-sectional area was measured at five predetermined points in the stented coronary segment. The inflation pressure used in patients who underwent direct stent implantation was higher than that employed in those who underwent conventional angioplasty with predilatation (13+/-3 atm vs 10+/-2 atm; P=.005). RESULTS: Luminal and stent cross-sectional areas were greater in the group that did not undergo predilatation than in the group that did. Neointimal proliferation in the 5 sections analyzed along the axis of the stent was similar in the 2 groups. There was a weak linear relationship between the amount of plaque outside the stent and neointimal proliferation in both the group that underwent predilatation (r=0.37; P=.005) and the group that did not (r=0.33; P=.005). CONCLUSIONS: As with conventional angioplasty, the neointimal proliferation that occurred after direct stent implantation showed a diffuse homogeneous pattern along the length of the stent. There was a weak correlation between this proliferative response and the amount of plaque outside the stent.

Proliferación neointimal después de la implantación coronaria de stent sin predilatación / Neointimal tissue proliferation after coronary stent implantation without predilatation

Introducción y objetivos. En la implantación de stent con predilatación la ecografía intracoronaria ha demostrado que la reducción luminal tardía se debe a la proliferación neointimal. En la presente serie analizamos el grado y la distribución de la proliferación neointimal intra-stent después de la implantación sin predilatación, así como las variables implicadas en esta respuesta proliferativa. Material y método. Se analizó a 45 pacientes después de la implantación exitosa de un stent sin predilatación y 23 pacientes con lesiones de características clínicas y angiográficas similares después de la implantación de un stent con predilatación. La ecografía intracoronaria en el seguimiento se realizó a los 7,85 ± 2,81 meses. Se midieron las áreas transversales (AT) en 5 segmentos predeterminados del segmento con stent. En el grupo de stent directo se empleó una presión de hinchado mayor que en el grupo con predilatación (13 ± 3 atm frente a 10 ± 2 atm; p = 0,005).Resultados. Los AT luminal y del stent fueron mayores en el grupo sin predilatación que en el grupo con predilatación. La proliferación neointimal en los 5 segmentos a lo largo del eje axial del stent fue similar en los dos grupos. Se observó una ligera relación lineal entre la placa fuera del stent y la proliferación neointimal en el grupo con predilatación (r = 0,37; p = 0,005) y sin predilatación (r = 0,33; p = 0,005). Conclusiones. De forma similar a la angioplastia convencional, en el stent directo la respuesta neointimal presenta un patrón difuso y homogéneo a lo largo del eje longitudinal del stent. Esta respuesta proliferativa se correlacionó ligeramente con la placa excluida por el stent (AU)

Introduction and objectives. Intravascular ultrasound (IVUS) studies in conventional stent angioplasty with predilatation have demonstrated that late luminal narrowing is caused by neointimal proliferation. In the present study, we analyzed the degree and distribution of in-stent neointimal proliferation after direct stent implantation and aimed to identify variables that predict a proliferative response. Material and method. We studied 45 patients who underwent successful stent implantation without predilatation and 23 patients with similar clinical and angiographic characteristics who underwent conventional stent angioplasty with predilatation. IVUS imaging was performed at 7.85±2.81 months. The cross-sectional area was measured at five predetermined points in the stented coronary segment. The inflation pressure used in patients who underwent direct stent implantation was higher than that employed in those who underwent conventional angioplasty with predilatation (13±3 atm vs 10±2 atm; P=.005). Results. Luminal and stent cross-sectional areas were greater in the group that did not undergo predilatation than in the group that did. Neointimal proliferation in the 5 sections analyzed along the axis of the stent was similar in the 2 groups. There was a weak linear relationship between the amount of plaque outside the stent and neointimal proliferation in both the group that underwent predilatation (r=0.37; P=.005) and the group that did not (r=0.33; P=.005). Conclusions. As with conventional angioplasty, the neointimal proliferation that occurred after direct stent implantation showed a diffuse homogeneous pattern along the length of the stent. There was a weak correlation between this proliferative response and the amount of plaque outside the stent (AU)