Zinnia Executive and Leadership Team

May, 2026

Leadership Overview

Zinnia has 6 executives leading key functions including strategy, operations, technology, human resources, and staff support.

Driven by innovation, Zinnia is dedicated to advancing healthcare and wellness through technology, enhancing patient care and optimizing operational efficiency across the sector.

Leadership Roles at Zinnia

  • Founder & Chief Executive Officer - Eldana Sime
  • Chief of Staff - Callie Thomas
  • Chief Technology Officer - Bradley Medd
  • Operations Chief of Staff - Gregory Heinen
  • Director, Chief of Staff - David Siebold
  • Chief Human Resources Officer - Elaine Page
  • Eldana Sime - Founder & Chief Executive Officer

    Eldana Sime, the Founder & Chief Executive Officer at Zinnia, directs the company's overarching strategy and vision. Sime architects the long-term growth initiatives, ensuring Zinnia's solutions effectively address critical needs within the healthcare and wellness sectors. This leadership role involves guiding product development and market positioning to maximize patient care enhancements and operational efficiencies. By fostering a culture of innovation, Eldana Sime drives the company's commitment to pioneering advancements. The CEO's strategic oversight ensures alignment with market demands and regulatory landscapes, solidifying Zinnia's impact. Sime's executive decisions shape the company's trajectory, focusing on sustainable expansion and industry leadership. This position demands a comprehensive understanding of both technological capabilities and the nuanced requirements of healthcare operations. Eldana Sime's leadership is central to achieving Zinnia's mission of transforming healthcare delivery.

    Callie Thomas - Chief of Staff

    Callie Thomas, the Chief of Staff at Zinnia, manages strategic initiatives and operational alignment across departments. Thomas ensures seamless execution of the CEO's directives, facilitating cross-functional collaboration to drive Zinnia's mission forward. This role involves optimizing internal processes and supporting key decision-making frameworks. By coordinating project timelines and resource allocation, Callie Thomas enhances overall organizational effectiveness. The Chief of Staff acts as a key liaison, bridging communication between executive leadership and operational teams. Thomas's focus remains on improving workflow efficiency and supporting the strategic objectives of Zinnia's healthcare and wellness solutions. This position requires meticulous planning and a deep understanding of Zinnia's business model. Callie Thomas's contributions are vital for maintaining momentum and achieving targeted outcomes in patient care and operational improvements.

    Bradley Medd - Chief Technology Officer

    Bradley Medd, the Chief Technology Officer at Zinnia, spearheads the company's technological innovation and infrastructure development. Medd architects the technical roadmap, ensuring Zinnia's solutions deliver cutting-edge capabilities for healthcare and wellness. This leadership position involves overseeing all aspects of software engineering, data security, and platform scalability. By driving research and development, Bradley Medd ensures Zinnia remains at the forefront of technological advancement. The CTO's expertise is critical for enhancing patient care through robust digital tools and improving operational efficiency via advanced systems. Medd's strategic vision guides the integration of emerging technologies into Zinnia's product offerings. This role demands a profound understanding of complex IT systems and their application in regulated environments. Bradley Medd's technical leadership is fundamental to Zinnia's success in delivering impactful healthcare solutions.

    Gregory Heinen - Operations Chief of Staff

    Gregory Heinen, the Operations Chief of Staff at Zinnia, optimizes the company's operational frameworks and execution strategies. Heinen directs initiatives aimed at enhancing efficiency and streamlining workflows across Zinnia's healthcare and wellness technology services. This role focuses on improving the delivery mechanisms for patient care solutions and internal operational processes. By managing key operational projects, Gregory Heinen ensures that Zinnia's commitments are met with precision and timeliness. The Operations Chief of Staff collaborates closely with department heads to identify areas for improvement and implement best practices. Heinen's efforts are crucial for scaling Zinnia's impact and maintaining high standards of service delivery. This position requires a keen eye for process optimization and a strong understanding of operational dynamics. Gregory Heinen's leadership is essential for the smooth functioning and growth of Zinnia's operations.

    David Siebold - Director, Chief of Staff

    David Siebold, the Director, Chief of Staff at Zinnia, supports strategic planning and operational execution across the organization. Siebold facilitates the implementation of key projects and ensures alignment with Zinnia's core objectives in healthcare and wellness technology. This position involves coordinating cross-functional teams and driving progress on critical business initiatives. By managing stakeholder communications and project milestones, David Siebold enhances organizational coherence. The Director, Chief of Staff plays a pivotal role in translating strategic vision into actionable plans. Siebold's focus is on improving operational effectiveness and supporting the company's mission to advance patient care. This role demands strong organizational skills and a comprehensive grasp of Zinnia's business landscape. David Siebold's contributions are integral to Zinnia's operational success and strategic development.

    Elaine Page - Chief Human Resources Officer

    Elaine Page, the Chief Human Resources Officer at Zinnia, leads the company's talent strategy and organizational development initiatives. Page cultivates a robust company culture that supports Zinnia's mission in healthcare and wellness technology. This executive role involves overseeing recruitment, employee engagement, and professional development programs. By ensuring a skilled and motivated workforce, Elaine Page drives Zinnia's capacity to innovate and deliver exceptional patient care solutions. The CHRO's strategic direction is vital for attracting and retaining top talent in the competitive tech and healthcare sectors. Page's leadership focuses on fostering an environment where employees can thrive and contribute to Zinnia's growth. This position requires expertise in human capital management and a deep understanding of organizational dynamics. Elaine Page's commitment to people is fundamental to Zinnia's sustained success and operational excellence.
    Elaine Page

    Explore Leadership Teams in Healthcare Software

    Frequently Asked Questions Regarding Zinnia Top Executives and Leadership Team

    Who leads Zinnia?
    Zinnia is led by Eldana Sime (Founder & Chief Executive Officer), along with executives such as Callie Thomas (Chief of Staff) and Bradley Medd (Chief Technology Officer).
    Who is part of Zinnia’s executive team?
    The executive team of Zinnia includes leaders such as Eldana Sime (Founder & Chief Executive Officer), Callie Thomas (Chief of Staff), Bradley Medd (Chief Technology Officer) and other senior executives.
    How many executives does Zinnia have?
    Zinnia has 6 executives leading key business areas.
    What roles are included in Zinnia’s leadership team?
    The leadership team of Zinnia includes roles such as Founder & Chief Executive Officer, Chief of Staff, Chief Technology Officer, Operations Chief of Staff, Director, Chief of Staff.