10-vascular

10 - vascular

ABI and PWV are measured in the Human Phenotype Project to assess vascular health. ABI is a ratio of the systolic blood pressure in the ankle to the systolic blood pressure in the arm. PWV is the speed at which the pulse wave of the blood pressure travels along the wall of an artery or a combined length of arteries.

ABI

Ankle-Brachial Index (ABI) measurements were conducted using the Falcon (Viasonix, Israel) device while subjects were in supine position. During the ABI test, primary systolic pressures are measured in each of the right and left brachial arteries, and right and left ankles. ABI is determined as the ratio between the brachial systolic pressure and the ankle pressure on each side providing ABI values per each side. The systolic pressures were based on a combination of blood pressure cuffs and blood flow reading with photoplethysmograph (PPG) sensors placed on the measured limb fingers. Under normal circumstances, the blood pressure in the ankle will be very similar or identical to that measured in the arm, so the measured ABI value will be close to 1. In the case of peripheral arterial disease, there will be a discrepancy - the blood pressure at the ankle will be lower than the blood pressure in the arms. This will indicate insufficiency in the arteries that carry blood to the legs. In the general population, PAD affects about 10% of people over the age of 55.

PWV

Pulse wave velocity (PWV) is considered a surrogate marker for arterial stiffness/elasticity, which is correlated with vascular disease (REF). Vascular elasticity is important for the normal vascular function for attenuation and smoothing of the pulsation intensity and blood flow. With age, and in combination with atherosclerosis processes, blood vessels may lose their elasticity and become stiff. Increased arterial stiffness can predict future vascular system problems.The contractions of the heart generate arterial blood pressure pulse waves which propagate through the arterial walls. PWV is defined as the velocity at which these arterial blood pressure pulses propagate. PWV is a quantitative parameter reflecting arterial stiffness. Higher PWV values reflect greater than normal arterial stiffness. While there is no one set standard of how or where to measure PWV, some of the more common PWV measurements include the baPWV, which reflects the pulse wave propagation between the brachial and ankle, cfPWV reflecting propagation between the carotid and femoral, and faPWV also know as leg PWV reflecting the PWV along the leg between the femoral and ankle. In the HPP we measure leg PWV (faPWV). PWV is highly dependent on the method of measurement, as well as on the measurement sites. Therefore, typical values for baPWV differ from faPWV and cfPWV. Based on literature reports, normal PWV values can range between around 6 m/s to 14 m/s, depending on the method of measurement, location and the patient’s age. For example, according to Laurent et al. the PWV increases from 4–5 m/s in the ascending aorta to 5–6 m/s in the abdominal aorta then 8–9 m/s in the iliac and femoral arteries (Laurent et al. European Heart Journal (2006) 27, 2588–2605)

PWV has been recognized as an indicator of organ damage and a useful additional test in the investigation of high blood pressure, it is also a useful method for prediction of cardiovascular events and mortality. Studies have also shown that ABI is a reliable predictor of cardiovascular disease and mortality in patients with peripheral artery disease.

The information is stored in 1 parquet file: vascular.parquet

from pheno_utils import PhenoLoader
dl = PhenoLoader('vascular', age_sex_dataset=None)
dl
DataLoader for vascular with
15 fields
1 tables: ['vascular']
dl.dict
field_string description_string parent_dataframe relative_location value_type units sampling_rate item_type array cohorts data_type debut pandas_dtype
tabular_field_name
collection_timestamp Collection timestamp Collection timestamp NaN vascular.parquet Date Time NaN Data Single 10K Tabular 2019-01-29 datetime64[ns, Asia/Jerusalem]
collection_date Collection date (YYYY-MM-DD) Date NaN vascular.parquet Date Time NaN Data Single 10K Tabular 2019-01-29 datetime64[ns]
timezone Timezone Timezone NaN vascular.parquet NaN NaN NaN NaN NaN NaN NaN NaN string
r_ankle_pressure Right ankle pressure Systolic pressure value in the right ankle NaN vascular.parquet Continuous mmHg NaN Data Single 10K Tabular 2019-01-29 float
l_ankle_pressure Left ankle pressure Systolic pressure value in the left ankle NaN vascular.parquet Continuous mmHg NaN Data Single 10K Tabular 2019-01-29 float
r_brachial_pressure Right brachial pressure Systolic pressure value in the right brachial NaN vascular.parquet Continuous mmHg NaN Data Single 10K Tabular 2019-01-29 float
l_brachial_pressure Left brachial pressure Systolic pressure value in the left brachial NaN vascular.parquet Continuous mmHg NaN Data Single 10K Tabular 2019-01-29 float
r_abi Right ABI ABI in the left side (right ankle to right bra... NaN vascular.parquet Continuous ratio NaN Data Single 10K Tabular 2019-01-29 float
l_abi Left ABI ABI in the right side (left ankle to left brac... NaN vascular.parquet Continuous ratio NaN Data Single 10K Tabular 2019-01-29 float
from_r_thigh_to_r_ankle_transit_time From r thigh to r ankle transit time From right thigh to right ankle transit time NaN vascular.parquet Continuous miliseconds NaN Data Single 10K Tabular 2019-01-29 float
from_r_thigh_to_r_ankle_distance From r thigh to r ankle distance From right thigh to right ankle distance NaN vascular.parquet Continuous cm NaN Data Single 10K Tabular 2019-01-29 float
from_r_thigh_to_r_ankle_pwv PWV (from right thigh to right ankle) Pulse Wave Velocity NaN vascular.parquet Continuous m/s NaN Data Single 10K Tabular 2019-01-29 float
from_l_thigh_to_l_ankle_transit_time From l thigh to l ankle transit time Time between pressure upstroke in the left thi... NaN vascular.parquet Continuous miliseconds NaN Data Single 10K Tabular 2019-01-29 float
from_l_thigh_to_l_ankle_distance From l thigh to l ankle distance Manually measured distance between proximal si... NaN vascular.parquet Continuous cm NaN Data Single 10K Tabular 2019-01-29 float
from_l_thigh_to_l_ankle_pwv PWV (from left thigh to left ankle) Calculated left leg PWV NaN vascular.parquet Continuous m/s NaN Data Single 10K Tabular 2019-01-29 float