The SHAPE study is a prospective, randomized study evaluating changes in cardiac function in adult patients undergoing cardiac surgery with cardiopulmonary bypass. The study focuses on how cardiac function changes during surgery and whether the depth of anesthesia may influence these changes. Participants are randomly assigned to one of two levels of anesthesia depth, guided by the Bispectral Index (BIS). Cardiac function is assessed using transthoracic echocardiography, including myocardial deformation (strain) imaging and myocardial work measurements. Invasive hemodynamic measurements obtained during surgery are also recorded. The primary objective is to assess the change in left ventricular global longitudinal strain (LV GLS) between two intraoperative time points: after induction of anesthesia and before cardiopulmonary bypass, and after separation from cardiopulmonary bypass. The study will also examine whether these changes differ according to the assigned depth of anesthesia and whether echocardiographic and hemodynamic measurements are associated with postoperative outcomes. Participants will also undergo follow-up echocardiographic assessment at 3, 6, and 12 months after surgery to evaluate longer-term changes in cardiac function.
The SHAPE study is a prospective, randomized, parallel-group, single-masked interventional study conducted in adult patients undergoing elective cardiac surgery with cardiopulmonary bypass. The study is designed to investigate perioperative changes in myocardial function and to assess the potential influence of anesthesia depth on these changes. Participants are randomized in a 1:1 ratio to two Bispectral Index (BIS)-guided anesthesia strategies: a BIS target of 45-55, representing standard anesthesia depth, or a BIS target of 30-35, representing deeper anesthesia. Total intravenous anesthesia with propofol and remifentanil is adjusted by the treating anesthesiologist to maintain the assigned BIS range. The echocardiographic outcome assessor remains blinded to treatment allocation during image acquisition, offline echocardiographic analysis, and primary outcome assessment. Cardiac function is evaluated using transthoracic echocardiography and speckle-tracking analysis. Measurements include left ventricular global longitudinal strain (LV GLS), myocardial work indices, and additional indices of left- and right-sided cardiac function. Invasive hemodynamic monitoring using a Swan-Ganz catheter provides measurements including pulmonary capillary wedge pressure, cardiac output, cardiac index, pulmonary artery pressure, and right atrial pressure. The primary analysis evaluates the within-participant change in LV GLS between two predefined intraoperative time points: after induction of anesthesia and before initiation of cardiopulmonary bypass (T1), and after separation from cardiopulmonary bypass (T2). Secondary analyses will assess whether the magnitude of perioperative changes in LV GLS and myocardial work differs between the two randomized BIS groups and will explore associations between echocardiographic measurements, invasive hemodynamic parameters, and postoperative clinical outcomes. Postoperative outcomes include low cardiac output syndrome, requirement for inotropic or vasopressor support, postoperative atrial fibrillation, duration of mechanical ventilation, and length of intensive care unit stay. Echocardiographic follow-up is performed at 3, 6, and 12 months after surgery to assess longer-term changes in cardiac function.
Study Type
INTERVENTIONAL
Allocation
RANDOMIZED
Purpose
BASIC_SCIENCE
Masking
SINGLE
Enrollment
70
Total intravenous anesthesia with propofol and remifentanil will be adjusted by the treating anesthesiologist to maintain a Bispectral Index (BIS) target range of 45-55, representing standard anesthesia depth.
Total intravenous anesthesia with propofol and remifentanil will be adjusted by the treating anesthesiologist to maintain a Bispectral Index (BIS) target range of 30-35, representing deeper anesthesia.
AHEPA University General Hospital of Thessaloniki
Thessaloniki, Greece
RECRUITINGWithin-Participant Change in Left Ventricular Global Longitudinal Strain (LV GLS) From T1 to T2
Left ventricular global longitudinal strain (LV GLS) will be assessed by speckle-tracking echocardiography at two predefined intraoperative time points: T1, after induction of anesthesia and before initiation of cardiopulmonary bypass, and T2, after separation from cardiopulmonary bypass. The primary outcome will be the within-participant change in LV GLS, calculated as T2 minus T1 and expressed in percentage points. Because LV GLS is expressed as a negative value, a positive T2-minus-T1 difference indicates a reduction in the absolute magnitude of LV GLS and therefore deterioration in longitudinal systolic function.
Time frame: During index cardiac surgery: T1 after induction of anesthesia and before cardiopulmonary bypass; T2 after separation from cardiopulmonary bypass.
Change in Left Ventricular Global Longitudinal Strain (LV GLS) From T1 to T2 by Randomized BIS Group
Left ventricular global longitudinal strain (LV GLS) will be assessed by speckle-tracking echocardiography at T1, after induction of anesthesia and before cardiopulmonary bypass, and at T2, after separation from cardiopulmonary bypass. The within-participant change in LV GLS (T2 minus T1), expressed in percentage points, will be compared between participants randomized to the BIS 45-55 and BIS 30-35 groups.
Time frame: During index cardiac surgery: from T1 before cardiopulmonary bypass to T2 after separation from cardiopulmonary bypass.
Change in Left Ventricular Myocardial Work Indices From T1 to T2 by Randomized BIS Group
Left ventricular myocardial work will be assessed using non-invasive pressure-strain loops at T1, after induction of anesthesia and before cardiopulmonary bypass, and at T2, after separation from cardiopulmonary bypass. Myocardial work indices will include Global Work Index (GWI), Global Constructive Work (GCW), Global Wasted Work (GWW), and Global Work Efficiency (GWE). Changes from T1 to T2 will be assessed within participants and compared between the BIS 45-55 and BIS 30-35 groups.
Time frame: During index cardiac surgery: from T1, before cardiopulmonary bypass, to T2, after separation from cardiopulmonary bypass.
Postoperative Adverse Clinical Events
Postoperative adverse clinical events will include the occurrence of low cardiac output syndrome (LCOS), requirement for inotropic or vasopressor support, and postoperative atrial fibrillation (POAF). Each event will be recorded during the postoperative hospitalization and evaluated in relation to perioperative echocardiographic, hemodynamic, and anesthesia-related parameters.
Time frame: From completion of index cardiac surgery through discharge during the index hospitalization, assessed up to 60 days after surgery.
Duration of Mechanical Ventilation
The duration of postoperative mechanical ventilation will be recorded as the time from completion of index cardiac surgery until successful extubation. Duration will be expressed in minutes and analyzed in relation to perioperative echocardiographic, hemodynamic, and anesthesia-related parameters.
Time frame: From completion of index cardiac surgery until successful extubation during the index hospitalization, assessed up to 60 days after surgery.
Length of Intensive Care Unit Stay
The length of stay in the intensive care unit (ICU) will be recorded as the duration from postoperative admission to the ICU until discharge from the ICU. Duration will be expressed in days and analyzed in relation to perioperative echocardiographic, hemodynamic, and anesthesia-related parameters.
Time frame: From postoperative ICU admission until ICU discharge during the index hospitalization, assessed up to 60 days after surgery.
Change in Left Ventricular Global Longitudinal Strain During Follow-up
Left ventricular global longitudinal strain (LV GLS) will be assessed by speckle-tracking transthoracic echocardiography and expressed as a percentage (%). LV GLS will be measured preoperatively and reassessed at 3, 6, and 12 months after cardiac surgery. Changes at each follow-up time point will be evaluated relative to the preoperative baseline value.
Time frame: Preoperative baseline and 3, 6, and 12 months after index cardiac surgery.
Change in Left Ventricular Global Work Index During Follow-up
Left ventricular Global Work Index (GWI) will be assessed using non-invasive pressure-strain loop analysis and expressed in mmHg%. GWI will be measured preoperatively and reassessed at 3, 6, and 12 months after cardiac surgery. Changes at each follow-up time point will be evaluated relative to the preoperative baseline value.
Time frame: Preoperative baseline and 3, 6, and 12 months after index cardiac surgery.
Change in Left Ventricular Global Constructive Work During Follow-up
Left ventricular Global Constructive Work (GCW) will be assessed using non-invasive pressure-strain loop analysis and expressed in mmHg%. GCW will be measured preoperatively and reassessed at 3, 6, and 12 months after cardiac surgery. Changes at each follow-up time point will be evaluated relative to the preoperative baseline value.
Time frame: Preoperative baseline and 3, 6, and 12 months after index cardiac surgery.
Change in Left Ventricular Global Wasted Work During Follow-up
Left ventricular Global Wasted Work (GWW) will be assessed using non-invasive pressure-strain loop analysis and expressed in mmHg%. GWW will be measured preoperatively and reassessed at 3, 6, and 12 months after cardiac surgery. Changes at each follow-up time point will be evaluated relative to the preoperative baseline value.
Time frame: Preoperative baseline and 3, 6, and 12 months after index cardiac surgery.
Change in Left Ventricular Global Work Efficiency During Follow-up
Left ventricular Global Work Efficiency (GWE) will be assessed using non-invasive pressure-strain loop analysis and expressed as a percentage (%). GWE will be measured preoperatively and reassessed at 3, 6, and 12 months after cardiac surgery. Changes at each follow-up time point will be evaluated relative to the preoperative baseline value.
Time frame: Preoperative baseline and 3, 6, and 12 months after index cardiac surgery.
Change in Right Ventricular Free-Wall Strain During Follow-up
Right ventricular free-wall strain (RV FWS) will be assessed by speckle-tracking transthoracic echocardiography and expressed as a percentage (%). RV FWS will be measured preoperatively and reassessed at 3, 6, and 12 months after cardiac surgery. Changes at each follow-up time point will be evaluated relative to the preoperative baseline value.
Time frame: Preoperative baseline and 3, 6, and 12 months after index cardiac surgery.
Change in Right Atrial Strain During Follow-up
Right atrial strain (RA strain) will be assessed by speckle-tracking transthoracic echocardiography and expressed as a percentage (%). RA strain will be measured preoperatively and reassessed at 3, 6, and 12 months after cardiac surgery. Changes at each follow-up time point will be evaluated relative to the preoperative baseline value.
Time frame: Preoperative baseline and 3, 6, and 12 months after index cardiac surgery.
Change in Tricuspid Annular Plane Systolic Excursion During Follow-up
Tricuspid annular plane systolic excursion (TAPSE) will be assessed by transthoracic echocardiography and expressed in millimeters (mm). TAPSE will be measured preoperatively and reassessed at 3, 6, and 12 months after cardiac surgery. Changes at each follow-up time point will be evaluated relative to the preoperative baseline value.
Time frame: Preoperative baseline and 3, 6, and 12 months after index cardiac surgery.
Presence of Paradoxical Septal Motion During Follow-up
Interventricular septal motion will be assessed by transthoracic echocardiography and classified according to the presence or absence of paradoxical septal motion (PSM). PSM status will be recorded preoperatively and reassessed at 3, 6, and 12 months after cardiac surgery to evaluate its postoperative evolution.
Time frame: Preoperative baseline and 3, 6, and 12 months after index cardiac surgery.
Change in TAPSE/sPAP Ratio During Follow-up
The ratio of tricuspid annular plane systolic excursion to systolic pulmonary artery pressure (TAPSE/sPAP), an echocardiographic index of right ventricular-pulmonary arterial coupling, will be assessed by transthoracic echocardiography and expressed in mm/mmHg. The TAPSE/sPAP ratio will be measured preoperatively and reassessed at 3, 6, and 12 months after cardiac surgery. Changes at each follow-up time point will be evaluated relative to the preoperative baseline value.
Time frame: Preoperative baseline and 3, 6, and 12 months after index cardiac surgery.
Correlation Between Left Ventricular Global Longitudinal Strain and Pulmonary Capillary Wedge Pressure
Left ventricular global longitudinal strain (LV GLS) will be assessed by speckle-tracking transthoracic echocardiography and expressed as a percentage (%). Pulmonary capillary wedge pressure (PCWP) will be measured invasively using a Swan-Ganz catheter and expressed in mmHg. Both measurements will be obtained at T1, after induction of anesthesia and before cardiopulmonary bypass, and at T2, after separation from cardiopulmonary bypass. The correlation between LV GLS and PCWP will be assessed at each time point using Pearson's or Spearman's correlation coefficient, as appropriate.
Time frame: During index cardiac surgery at T1, after induction of anesthesia and before cardiopulmonary bypass, and at T2, after separation from cardiopulmonary bypass.
Correlation Between Left Ventricular Global Work Index and Pulmonary Capillary Wedge Pressure
Left ventricular Global Work Index (GWI) will be assessed using non-invasive pressure-strain loop analysis and expressed in mmHg%. Pulmonary capillary wedge pressure (PCWP) will be measured invasively using a Swan-Ganz catheter and expressed in mmHg. Both measurements will be obtained at T1, after induction of anesthesia and before cardiopulmonary bypass, and at T2, after separation from cardiopulmonary bypass. The correlation between GWI and PCWP will be assessed at each time point using Pearson's or Spearman's correlation coefficient, as appropriate.
Time frame: During index cardiac surgery at T1, after induction of anesthesia and before cardiopulmonary bypass, and at T2, after separation from cardiopulmonary bypass.
Correlation Between Left Ventricular Global Constructive Work and Pulmonary Capillary Wedge Pressure
Left ventricular Global Constructive Work (GCW) will be assessed using non-invasive pressure-strain loop analysis and expressed in mmHg%. Pulmonary capillary wedge pressure (PCWP) will be measured invasively using a Swan-Ganz catheter and expressed in mmHg. Both measurements will be obtained at T1, after induction of anesthesia and before cardiopulmonary bypass, and at T2, after separation from cardiopulmonary bypass. The correlation between GCW and PCWP will be assessed at each time point using Pearson's or Spearman's correlation coefficient, as appropriate.
Time frame: During index cardiac surgery at T1, after induction of anesthesia and before cardiopulmonary bypass, and at T2, after separation from cardiopulmonary bypass.
Correlation Between Left Ventricular Global Wasted Work and Pulmonary Capillary Wedge Pressure
Left ventricular Global Wasted Work (GWW) will be assessed using non-invasive pressure-strain loop analysis and expressed in mmHg%. Pulmonary capillary wedge pressure (PCWP) will be measured invasively using a Swan-Ganz catheter and expressed in mmHg. Both measurements will be obtained at T1, after induction of anesthesia and before cardiopulmonary bypass, and at T2, after separation from cardiopulmonary bypass. The correlation between GWW and PCWP will be assessed at each time point using Pearson's or Spearman's correlation coefficient, as appropriate.
Time frame: During index cardiac surgery at T1, after induction of anesthesia and before cardiopulmonary bypass, and at T2, after separation from cardiopulmonary bypass.
Correlation Between Left Ventricular Global Work Efficiency and Pulmonary Capillary Wedge Pressure
Left ventricular Global Work Efficiency (GWE) will be assessed using non-invasive pressure-strain loop analysis and expressed as a percentage (%). Pulmonary capillary wedge pressure (PCWP) will be measured invasively using a Swan-Ganz catheter and expressed in mmHg. Both measurements will be obtained at T1, after induction of anesthesia and before cardiopulmonary bypass, and at T2, after separation from cardiopulmonary bypass. The correlation between GWE and PCWP will be assessed at each time point using Pearson's or Spearman's correlation coefficient, as appropriate.
Time frame: During index cardiac surgery at T1, after induction of anesthesia and before cardiopulmonary bypass, and at T2, after separation from cardiopulmonary bypass.
Correlation Between Preoperative Right Atrial Strain and Intraoperative Pulmonary Capillary Wedge Pressure
Preoperative right atrial strain (RA strain) will be assessed by speckle-tracking transthoracic echocardiography and expressed as a percentage (%). Pulmonary capillary wedge pressure (PCWP) will be measured invasively using a Swan-Ganz catheter at T1 and expressed in mmHg. The correlation between preoperative RA strain and PCWP will be assessed using Pearson's or Spearman's correlation coefficient, as appropriate.
Time frame: Preoperative transthoracic echocardiography within 24 hours before surgery and intraoperative PCWP assessment at T1, after induction of anesthesia and before cardiopulmonary bypass.
Correlation Between Preoperative Right Atrial Strain and Intraoperative Cardiac Index
Preoperative right atrial strain (RA strain) will be assessed by speckle-tracking transthoracic echocardiography and expressed as a percentage (%). Cardiac index (CI) will be measured invasively using a Swan-Ganz catheter at T1 and expressed in L/min/m². The correlation between preoperative RA strain and CI will be assessed using Pearson's or Spearman's correlation coefficient, as appropriate.
Time frame: Preoperative transthoracic echocardiography within 24 hours before surgery and intraoperative cardiac index assessment at T1, after induction of anesthesia and before cardiopulmonary bypass.
Correlation Between Preoperative Right Ventricular Free-Wall Strain and Intraoperative Pulmonary Capillary Wedge Pressure
Preoperative right ventricular free-wall strain (RV FWS) will be assessed by speckle-tracking transthoracic echocardiography and expressed as a percentage (%). Pulmonary capillary wedge pressure (PCWP) will be measured invasively using a Swan-Ganz catheter at T1 and expressed in mmHg. The correlation between preoperative RV FWS and PCWP will be assessed using Pearson's or Spearman's correlation coefficient, as appropriate.
Time frame: Preoperative transthoracic echocardiography within 24 hours before surgery and intraoperative PCWP assessment at T1, after induction of anesthesia and before cardiopulmonary bypass.
Correlation Between Preoperative Right Ventricular Free-Wall Strain and Intraoperative Cardiac Index
Preoperative right ventricular free-wall strain (RV FWS) will be assessed by speckle-tracking transthoracic echocardiography and expressed as a percentage (%). Cardiac index (CI) will be measured invasively using a Swan-Ganz catheter at T1 and expressed in L/min/m². The correlation between preoperative RV FWS and CI will be assessed using Pearson's or Spearman's correlation coefficient, as appropriate.
Time frame: Preoperative transthoracic echocardiography within 24 hours before surgery and intraoperative cardiac index assessment at T1, after induction of anesthesia and before cardiopulmonary bypass.
Correlation Between Preoperative TAPSE/sPAP Ratio and Intraoperative Pulmonary Capillary Wedge Pressure
The preoperative TAPSE/sPAP ratio will be assessed by transthoracic echocardiography and expressed in mm/mmHg. Pulmonary capillary wedge pressure (PCWP) will be measured invasively using a Swan-Ganz catheter at T1 and expressed in mmHg. The correlation between the preoperative TAPSE/sPAP ratio and PCWP will be assessed using Pearson's or Spearman's correlation coefficient, as appropriate.
Time frame: Preoperative transthoracic echocardiography within 24 hours before surgery and intraoperative PCWP assessment at T1, after induction of anesthesia and before cardiopulmonary bypass.
Correlation Between Preoperative TAPSE/sPAP Ratio and Intraoperative Cardiac Index
The preoperative TAPSE/sPAP ratio will be assessed by transthoracic echocardiography and expressed in mm/mmHg. Cardiac index (CI) will be measured invasively using a Swan-Ganz catheter at T1 and expressed in L/min/m². The correlation between the preoperative TAPSE/sPAP ratio and CI will be assessed using Pearson's or Spearman's correlation coefficient, as appropriate.
Time frame: Preoperative transthoracic echocardiography within 24 hours before surgery and intraoperative cardiac index assessment at T1, after induction of anesthesia and before cardiopulmonary bypass.
Correlation Between Preoperative E/LA Strain Ratio and Intraoperative Pulmonary Capillary Wedge Pressure
The preoperative E/LA strain ratio will be calculated as the ratio of early diastolic transmitral flow velocity (E), measured by pulsed-wave Doppler echocardiography and expressed in cm/s, to left atrial strain, measured by speckle-tracking transthoracic echocardiography and expressed as a percentage (%). The E/LA strain ratio will be expressed in cm/s/%. Pulmonary capillary wedge pressure (PCWP) will be measured invasively using a Swan-Ganz catheter at T1 and expressed in mmHg. The correlation between the preoperative E/LA strain ratio and intraoperative PCWP will be assessed using Pearson's or Spearman's correlation coefficient, as appropriate.
Time frame: Preoperative transthoracic echocardiography within 24 hours before surgery and intraoperative PCWP assessment at T1, after induction of anesthesia and before cardiopulmonary bypass.
This platform is for informational purposes only and does not constitute medical advice. Always consult a qualified healthcare professional.